Siddharth Bhat

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1. Implementing Nelson Oppen
2. Nondeterministic Nelson Oppen
3. Gosper's algorithm
4. WZ (Wilf Zeilberger) pairs
5. Software bugs are real bugs?
6. Sister Celine's Algorithm
7. I like piano sonatas
8. I like New Formalism Poetry
9. Kinds of Fiction Genres I Like
10. The Two Modes of my Work
11. The Gradual Guarantees
12. Lean Naming Convention for Contexts
13. Right hand for arpeggios
14. Simulating Inductives Via Coinductives (And Vice Versa)
15. Amelie Arpeggiation Explanation
16. Inductive Predicate as Least Fixed Point, directly
17. Interpolants: Vibes
18. AWS MathFest 2024
19. Proving False with partial functions even with Inhabited types
20. Table Maker's Dilemma
21. Techne, Da Vinci, Michalangelo, and Art
22. Ffmpeg one liner to re-encode mp4 so chrome can open it
23. Notes on Copy and Patch Compilation
24. Setting up SAIL for porting to Lean
25. Gregorian chant and numes
26. Decreasing Metric for Mutual Recursive Functions
27. FOL + Fixpoint + Counting does not capture P
28. Building an ELF by hand
29. Resolution is Refutation Complete
30. Fagin's theorem
31. EF (Ehrenfeucht–Fraïssé) games
32. DPLL
33. Why FOL models must be nonempty
34. Concrete calculation of hopf fibration
35. Canonical bundle over RP2 is not trivial
36. Concrete description of spinors
37. Paracompact spaces
38. Latin prefixes for words
39. Crash Course on Prosody
40. What the hell is a nix flake?
41. How to prove noConfusion
42. Origami box pleating
43. Vibes of Weiner Processes
44. Forward versus backward euler
45. Uniform Boundedness Principle / Banach Steinhauss
46. Coercive operator
47. It suffices to check for weak convergence on a spanning set.
48. Sequence that converges weakly but not strongly in $l^p$.
49. Axioms for definite integration
50. Quotient spaces of Banach space
51. Reisez Lemma
52. Using LLL to discover minimal polynomial for floating point number
53. Total Boundedness in a metric space
54. Holonomic v/s non holonomic constraints
55. The Plenoptic Function
56. Precision, Recall, and all that.
57. Heine Borel
58. The conceit of self loathing
59. Inverse scattering transform
60. Differentiating through sampling from a random normal distribution
61. BOSCC Vectorization
62. Autodiff
63. Vector Bundles and K theory, 1.1
64. Equicontinuity, Arzela Ascoli
65. Sobolev Embedding Theorem
66. Eikonal Equation [WIP ]
67. Practical example of semidirect product
68. Algebraic graph calculus
69. Change of basis from triangle x y to barycentric
70. Lean4 access metam and so forth
71. Harmonic function
72. Lax Milgram theorem
73. Why L2 needs a quotient upto almost everywhere
74. Repulsive curves
75. Why NuPRL and Realisability makes it hard to communicate math
76. Lean does not allow nested inductive families
77. Weakly implicit arguments in Lean
78. Big list of elf file munging / linker / ABI
79. Regular epi and regular category
80. Focal point
81. Operational versus Denotational semantics
82. Minimising L2 norm with total constraint
83. Bounding L2 norm by L1 norm and vice versa
84. Example of unbounded linear operator
85. Direct sum of topological vector spaces
86. Subspaces need not have complement
87. $L^\infty$ is HUGE
88. Banach space that does not admit Schrauder basis
89. Open mapping theorem
90. Closed graph theorem
91. Bounded inverse theorem
92. Nonexistence of solutions for ODE and PDE
93. Baire Category Theorem
94. libOpenGL, libVDSO and Nix
95. Stuff I learnt in 2022
96. You don't know jack about data races
97. Training a custom model for Lean4
98. Stratified synthetsis
99. Mutual recursion elaboration in Lean
100. Subject reduction in Lean
101. Big list of GNU Binutils
102. Axiom K versus UIP
103. Linear vs uniqueness types
104. Any model of lean must have all inductives
105. Index over the past, fiber over the future
106. Type formers need not be injective
107. There cannot be a type of size the universe
108. The dependently typed expression problem
109. Motivation for modal logic
110. Scones
111. Presheaf models of type theory
112. Weighted limits via collages
113. Disjoint Coproduct
114. Leibniz Equality in Lean4
115. Strong normalization of STLC
116. Subobject classifiers of $N \to FinSet$, or precosheaf of $FinSet$
117. Dimensions versus units
118. HoTTesT: Identity types
119. Left and right adjoints to inverse image
120. Paredit via adjoints
121. Less than versus Less than or equals over Z
122. Allegories and Categories
123. Partial function as span
124. Turing degree
125. Proof that there is a TM whose halting is independent of ZFC
126. Contradiction from non-positive occurence
127. The constructible universe L
128. Godel completeness theorem
129. Uniform proofs, focused proofs, polarization, logic programming
130. Why cut elimination?
131. Forcing to add a function
132. Diaconescu's theorem
133. Forcing machinery
134. Partial Evaluation, Chapter 3
135. Partial Evaluation, Chapter 1
136. Diagonal lemma for monotone functions
137. Cantor Schroder Bernstein via fixpoint
138. Maximal Ideals of Boolean Algebras are Truth Values
139. Crash course on DCPO: formalizing lambda calculus
140. Resolution algorithm for propositional logic
141. Completeness for first order logic
142. Compactness theorem of first order logic
143. First order logic: Semantics
144. full abstraction in semantics
145. You could have invented Sequents
146. Fibrational category theory, sec 1.1, sec 1.2
147. Simple Type Theory via Fibrations
148. Realisability models
149. Naming left closed, right open with start/stop
150. Nested vs mutual inductive types:
151. Embedding HOL in Lean
152. Module system for separate compilation
153. Second order arithmetic
154. Lean4 Dev Meeting
155. Categorical model of dependent types
156. Coends
157. Natural Transformations as ends
158. Ends and diagonals
159. Parabolic dynamics and renormalization
160. Quantifiers as adjoints
161. TLDP pages for bash conditionals
162. Remainder, Modulo
163. Parameters cannot be changed anywhere , not just in return location
164. LCNF
165. Predicative v/s Impredicative: On Universes in Type Theory
166. Testing infra in Lean4
167. Autocompletion in Lean4
168. Inductive types
169. Parameter verus Index
170. HNF versus WHNF
171. Different types of arguments in Lean4:
172. Big list of lean tactics
173. Hyperdoctrine
174. Fungrim
175. Category where coproducts of computable things is not computable
176. Homotopy continuation
177. Relationship between linearity and contradiction
178. Monads from Riehl
179. Combinatorial Cauchy Schwarz
180. Bezout's theorem
181. Example for invariant theory
182. Counterexample to fundamental theorem of calculus?
183. Why a sentinel of -1 is sensible
184. Data structure to maintain mex
185. Scatted algebraic number theory ideas: Ramification
186. Coreflection
187. Better man Pages via info
188. The Zen of juggling three balls
189. Example of lattice that is not distributive
190. Patat
191. Common Lisp LOOP Macro
192. Mitchell-Bénabou language
193. Hyperdoctrine
194. Why is product in Rel not cartesian product?
195. simp in Lean4
196. Big list of Lean4 TODOS
197. unsafePerformIO in Lean4:
198. Big List of Lean4 FAQ
199. Sheaves in geometry and logic 1.2: Pullbacks
200. Sheaves in geometry and logic 1.3: Characteristic functions of subobjects
201. Common Lisp Debugging: Clouseau
202. Drawabox: Lines
203. Common Lisp Beauty: paths
204. Logical Predicates (OPLSS '12)
205. Logical Relations (Sterling)
206. Pointless topology: Frames
207. Introduction to substructural logics: Ch1
208. Integrating against ultrafilers
209. wegli: Neat tool for semantically grepping C++
210. Mostowski Collapse
211. Spaces that have same homotopy groups but not the same homotopy type
212. Fundamental group functor does not preserve epis
213. Epi in topological spaces
214. Permutation models
215. Almost universal class
216. Godel operations
217. Orthogonal Factorization Systems
218. Orthogonal morphisms
219. Locally Presentable Category
220. Remez Algorithm
221. Permission bits reference
222. Papers on Computational Group Theory
223. Kan Extensions: Key idea
224. Interleaved dataflow analysis and rewriting
225. Central variable as focal
226. Wilson's theorem
227. General enough special cases
228. XOR and AND relationship
229. Geometry of complex integrals
230. Green's functions
231. CP trick: writing exact counting as counting less than
232. CP trick: Heavy Light Decomposition euler tour tree
233. Counting with repetitions via pure binomial coefficients
234. Fundamental theorem of homological algebra [TODO ]
235. Projective modules in terms of universal property
236. How ideals recover factorization [TODO ]
237. Centroid of a tree
238. Path query to subtree query
239. Pavel: bridges, articulation points for UNDIRECTED graphs
240. Monadic functor
241. Injective module
242. Proof that $Spec(R)$ is a sheaf [TODO ]
243. Projections onto convex sets
244. LM algorithm for nonlinear least squares
245. Backward dataflow and continuations
246. Coordinate compression with set and vector
247. Hilbert polynomial and dimension
248. Cost of looping over all multiples of $i$ for $i$ in $1$ to $N$
249. Stuff I learnt in 2021
250. Cayley hamilton for 2x2 matrices in sage via AG
251. LispWorks config
252. Birkhoff Von Neumann theorem
253. Latin Square
254. Assignment Problem
255. Interpolating homotopies
256. Example where MIP shows extra power over IP
257. Lazy reversible computation?
258. Theorem coverage as an analogue to code coverage
259. Lazy GPU programming
260. Backward dataflow and continuations
261. The tyranny of structurelessness
262. Simple Sabotage Field Manual
263. Counting permutations with #MAXSAT
264. Coloring cat output with supercat
265. Reader monoid needs a hopf algebra?!
266. Monads mnemonic
267. Card stacking
268. SSH into google cloud
269. Comma & Semicolon in index notation
270. Spin groups
271. Undefined behaviour is like compactification [TODO ]
272. God of areppo
273. Classification of lie algebras, dynkin diagrams
274. Weird free group construction from adjoint functor theorem
275. bashupload
276. When are the catalan numbers odd
277. Geodesic equation, Extrinsic
278. Connections, take 2
279. Dropping into tty on manjaro/GRUB
280. Why the zero set of a continuous function must be a closed set
281. Derivatives in diffgeo
282. Building stuff with Docker
283. Lie derivative versus covariant derivative
284. The Tor functor
285. Sum of quadratic errors
286. Hip-Hop and Shakespeare
287. Write thin to write well
288. Hidden symmetries of alg varieties
289. fd for find
290. Thu Morse sequence for sharing
291. Elementary and power sum symmetric polynomials
292. Projective spaces and grassmanians in AG
293. Mnemonic for why eta is unit:
294. Fundamental theorem of galois theory
295. Counter-intuitive linearity of expectation [TODO ]
296. Metis
297. Tooling for performance benchmarking
298. Normal field extensions
299. Eisenstein Theorem for checking irreducibility
300. Gauss Lemma for polynomials
301. How GHC does typeclass resolution
302. Defining continuity covariantly
303. Why commutator is important for QM
304. Deriving pratt parsing by analyzing recursive descent [TODO ]
305. Level set of a continuous function must be closed
306. HPNDUF - Hard problems need design up front!
307. Separable Extension is contained in Galois extension
308. Primitive element theorem
309. Separable extension via embeddings into alg. closure
310. Separable extensions via derivation
311. Irreducible polynomial over a field divides any polynomial with common root
312. Galois extension
313. Separability of field extension as diagonalizability
314. Motivation for the compact-open topology
315. Example of covariance zero, and yet "correlated"
316. Hypothesis Testing
317. Dumb mnemonic for remembering adjunction turnstile
318. Delta debugging
319. Tidy Data
320. Normal subgroups through the lens of actions
321. Writing rebuttals, Tobias style
322. LCS DP: The speedup is from filtration
323. Poisson distribution
324. F1 or Fun : The field with one element
325. McKay's proof of Cauchy's theorem for groups [TODO ]
326. ncdu for disk space measurement
327. nmon versus htop
328. Schrier sims --- why purify generators times coset
329. Vyn's feeling about symmetry
330. Convergence in distribution is very weak
331. Class equation, P-group structure
332. Sylow Theorem 1
333. Fuzzing book
334. Fisher Yates
335. Bucchberger algorithm
336. GAP permutation syntax
337. Why division algorithm with multiple variables go bad
338. Integral elements of a ring form a ring [TODO ]
339. "Cheap" proof of euler characteristic
340. Siefert Algorithm [TODO ]
341. Cap product [TODO ]
342. Cup product [TODO ]
343. Colimits examples with small diagram categories
344. Limits examples with small diagram categories
345. Classification of compact 2-manifolds [TODO ]
346. Gauss, normals, fundamental forms [TODO ]
347. Second fundamental form
348. Theorem Egregium / Gauss's theorem (Integrating curvature in 2D) [TODO ]
349. Integrating Curvature in 1D [TODO ]
350. Fundamental theorem of symmetric polynomials
351. DP over submasks
352. Dual of Planar Euler graph is bipartite
353. Yoneda preserves limits
354. Separable Polynomials and extensions
355. Limits of a functor category are computed pointwise.
356. a + b = (a or b) + (a and b)
357. Intuition for why choosing closed-closed intervals of [1..n] is $(n+1)C2$
358. Thoughtful discussion on the limits of safe spaces
359. Semidirect product: Panning and Zooming
360. Longest Convex Subsequence DP
361. Representation theory of $SU(2)$ [TODO ]
362. Why quaternions work better
363. DFA to CFG via colimits?
364. Why pointless topology is powerful
365. Denotational semantics in a few sentences
366. Monge Matrix
367. Fixpoint as decorator
368. Combinatorial generation algorithms
369. Perform DP on measures, not indexes.
370. Alternative version of Myhill-Nerode
371. Polya Enumeration
372. Weighted Burnside Lemma
373. Cycle index polynomial
374. Mnemonics For Symmetric Polynomials
375. Uses of minimal string rotation
376. Suffix Automata
377. Simpson's Paradox
378. Myhill Nerode Theorem
379. Linearity of expectation for sampling
380. Min cost flow (TODO)
381. Clojure: minimal makefile for REPL driven dev with Neovim
382. Delimited continuations
383. Never forget monic again
384. Weird canonical example of monic and epic: left/right shift
385. Playing guitar: being okay with incorrect chords
386. Sparse table
387. Duval's algorithm
388. Amortized complexity from the verifier perspective
389. Relationship betwee permutations and runs
390. Brouwer's fixed point theorem
391. XOR on binary trie
392. Inconvergent: beautiful generative art
393. Prefix/Border function
394. Shortest walk versus shortest path
395. Minimal tech stack
396. FFT
397. codeforces rating of some GMs
398. Continuum TTRPG
399. Words to know in target language
400. DP on subarrays
401. Vis editor cheat sheet
402. Mean, Median and Jensen's
403. The similarity between labellings and representations
404. L1 norm is greater than or equal to L2 norm
405. Z algorithm
406. For a given recurrence, what base cases do I need to implement?
407. Number of distinct numbers in a partition
408. Splitting $f(x) = y$ into indicators
409. Why searching for divisors upto sqrt(n) works
410. Heuristics for the prime number theorem
411. Sum of absolute differences of an array
412. GCD is at most difference of numbers
413. implementing GCD and LCM
414. Centroid of a tree
415. Center of a tree
416. Image unshredding as hamiltonian path
417. Distance between lines in nD
418. lower_bound binary search with closed intervals
419. Sliding window implementation style
420. Kawaii implementation of x = min(x, y)
421. CSES: Counting Towers
422. Smallest positive natural which can't be represented as sum of any subset of a set of naturals
423. Example of RVs that are pairwise but not 3-way independent.
424. Notes on Liam O Connor's thesis: Cogent
425. C++ lower_bound, upper_bound API
426. Books that impart mental models
427. Subarrays ~= prefixes
428. Operations with modular fractions
429. Modular inverse calculation
430. The number of pairs (a,b) such that ab≤x is O(xlogx)
431. DP as path independence
432. Binary search to find rightmost index which does not possess some property
433. Correctness of lower_bound search with half-open intervals
434. Greedy Coin change: proof by probing
435. Clean way to write burnside lemma
436. The groupoid interpretation of type theory
437. Mnemonics for free = left adjoint
438. Where to scratch a cat
439. Mnemonic for Specht module actions
440. Quotes from 'Braiding Sweetgrass'
441. Transfinite recursion: Proof
442. Transfinite induction: Proof
443. Thoughts on playing Em-Bm
444. An explanation for why permutations and linear orders are not naturally isomorphic
445. We can't define choice for finite sets in Haskell!
446. Geomean is scale independent
447. Thoughts on playing Em Bm.
448. Induction on natural numbers cannot be derived from other axioms
449. Ordinals and cardinals
450. Musing about Specht modules
451. Every continuous function on $[a, b]$ attains a maximum
452. Invisible cities
453. Associativity of addition in cubicaltt
454. Etymology of fiber bundle $F \rightarrow E \rightarrow B$
455. Galois correspondence, functorially
456. CubicalTT: sharpening thinking about indexed functions
457. Functors to motivate adjuntions
458. Madoka Magica: plot thoughts
459. Chain rule functorially
460. Lagrange multipliers by algebra
461. Specht module construction
462. Even and odd functions through representation theory
463. Greg egan: Orthogonal
464. Simplicial approximation: maps can be approximated by simplicial maps (TODO)
465. Limit is right adjoint to diagonal
466. Working out why right adjoints preserve limits.
467. Limit/Colimit/Cone/Cocone: the arrows are consistent!
468. Representable Functors
469. Why terminal object is a limit
470. Excluded middle is not false in intuitionistic logic
471. Yoneda Lemma and embedding
472. GHCID
473. Character theory
474. Cofibration
475. Emily Riehl Contrability as uniqueness
476. Cofactor as derivative of determinant
477. Homology, the big picture
478. Legal Systems very different from ours
479. Shrinking wedge of circles / Hawaiian earring (TODO)
480. Simplicial approxmation of maps (TODO)
481. Lebesgue number lemma (TODO)
482. Lean internals Cheat Sheet
483. MicroUI
484. Proof of tree having (V-1) edges
485. Creating PDFs to read code
486. Bias and gain
487. Barycentric subdivision: edge length decreases
488. Homotopic maps produce same singular homology: Intuition
489. Singular homology: induced homomorphism
490. Demoscene tools
491. Binaural Beat
492. Low pass filter by delaying
493. Octaves are double frequency apart (TODO)
494. Bias and gain
495. Show, don't tell
496. Try and think of natural transformations as intertwinings
497. Subobject classifier measures how much we need to pay to access fact
498. Spectral norm of Hermitian matrix equals largest eigenvalue (TODO)
499. Penrose cohomology [TODO ]
500. Weingarten map
501. When maps cannot be lifted to the universal cover
502. Nets from Munkres (TODO)
503. Limit point compactness from Munkres
504. Proof of Heine Borel from Munkres (compact iff closed, bounded)
505. Alexandrov topology
506. Zeroth singular homology group: Intuition
507. Examples of fiber products / pullbacks
508. Covariant derivative
509. Clackety sounds: bucklespring
510. Submersions and immersions
511. Ehrsmann connection
512. Quotes from the culture
513. Lie bracket commutator as infinitesimal conjugation
514. Thoughts on proof of fundamental group of unit circle
515. Pasting lemma
516. Tensoring with base ring has no effect
517. Seeing the semidirect product of the dihedral group.
518. Animating rotations with quaternion curves
519. Mnemonic for hom-tensor and left-right adjoints
520. Construction of tensor product: Atiyah macdonald
521. Recovering topology from sheaf of functions: Proof from Atiyah Macdonald
522. Urhyson's lemma
523. Compact Hausdorff spaces are normal
524. Stone representation theorem: Proof from Atiyah Macdonald
525. Covariant Hom is left exact
526. Internal versus External semidirect products
527. Splitting of semidirect products in terms of projections
528. Tensor is right exact
529. Semidirect product as commuting conditions
530. Exact sequences for semidirect products; fiber bundles
531. Semidirect product is equivalent to splitting of exact sequence
532. Intro to topological quantum field theory
533. Non examples of algebraic varieties
534. Nilradical is intersection of all prime ideals
535. Exactness of modules is local
536. Quotient by maximal ideal gives a field
537. Ring of power series with infinite positive and negative terms
538. Mean value theorem and Taylor's theorem. (TODO)
539. Cayley Hamilton
540. Nakayama's lemma
541. Vector fields over the 2 sphere
542. Learning to talk with your hands
543. Lovecraftisms
544. Hairy ball theorem from Sperner's Lemma (TODO)
545. CS and type theory: Talks by vovodesky
546. Hilbert basis theorem for polynomial rings over fields (TODO)
547. Covering spaces
548. Wedge Sum and Smash Product
549. Quotient topology
550. CW Complexes and HEP
551. Stable homotopy theory
552. Simply connected spaces
553. Finitely generated as vector space v/s algebra:
554. Weak and Strong Nullstllensatz
555. Screen recording for kakoune pull request
556. Intuition for why finitely presented abelian groups are isomorphic to product of cyclics
557. Euler characteristic of sphere
558. John Conway: The symmetries of things
559. Semidirect product mnemonic
560. Non orthogonal projections
561. Why did maxwell choose his EM wave to be light?
562. Fast string concatenation in python3
563. Split infinitive
564. Yoneda from string concatenation
565. Right Kan extensions as extending the domain of a functor
566. Non standard inner products and unitarity of representations
567. take at most 4 letters from 15 letters.
568. Flat functions
569. Hopf Algebras and combinatorics
570. Butcher group
571. Neovim frontends
572. A semidirect product worked on in great detail
573. Direct and Inverse limits
574. LEAN 4 overfrom from LEAN together 2021
575. BLM master thesis
576. RSK correspondence for permutations
577. Djikstra's using a segtree
578. Markov and chebyshev from a measure theoretic lens
579. Among any 51 integers, that are 2 with squares having equal value modulo 100
580. $1^n + 2^n + \dots + (n-1)^n$ is divisible by $n$ for odd $n$
581. $10^{3n+1}$ cannot be written as sum of two cubes
582. Coq-club: the meaning of a specification
583. SQLite opening
584. Old school fonts
585. Stalking syzigies on hackernews
586. Conditional probability is neither causal nor temporal
587. Hook length formula
588. The tyranny of light
589. Muirhead's inequality
590. Rearrangement inequality
591. Triangle inequality
592. The Heather subculture
593. Frobenius Kernel
594. Galois theory by "Abel's theorem in problems and solutions"
595. Galois theory perspective of the quadratic equation
596. Burnside lemma by representation theory.
597. Contributing to SAGEmath
598. Shadow puppet analogy for entanglement
599. Books for contest math
600. Analysing simple games
601. Linear algebraic proof of the handshaking lemma
602. Historical contemporaries
603. Rota's twelvefold way
604. Counting necklackes with unique elements
605. Decomposition of projective space
606. Childhood: Playing pokemon gold in japanese
607. Tensor is a thing that transforms like a tensor
608. Tensor Hom adjunction
609. Schur's lemma
610. Daughters of destiny
611. Stuff I learnt in 2020
612. Line bundles, a high level view as I understand them today
613. Conversations with a wood carver
614. Discrete Riemann Roch
615. Conversation with Olaf Klinke
616. Topological groups and languages
617. The mnemonica stack (TODO)
618. Conversation with Alok about how I read
619. KMP (Knuth, Morris, Pratt) (TODO)
620. Reading C declarations
621. Make mnemonics
622. Vandermonde and FFT
623. Thoughts on blitz chess: 950 ELO
624. Periodic tables and make illegal states unrepresentable
625. questions on the structure of graphs
626. Combinations notation in bijective combinatorics
627. Arguments for little endian
628. Expectiles
629. Depth first search through linear algebra (TODO)
630. 2-SAT
631. Longest increasing subsequence, step by step (TODO)
632. On reading how to rule (TODO)
633. Strongly Connected Components via Kosaraju's algorithm
634. Articulation points
635. Disjoint set union
636. Making GDB usable
637. Bouncing light clock is an hourglass
638. Euler tours
639. Representation theory of the symmetric group (TODO)
640. Maximum matchings in bipartite graphs
641. p-adics, 2's complement, intuition for bit fiddling
642. Diameter of a tree
643. Catalan numbers as popular candidate votes (TODO)
644. The chromatic polynomial (TODO)
645. Structure theory of finite endo-functions
646. Number of paths in a DAG
647. Set partitions
648. Integer partitions: Recurrence
649. Stars and bars by direct bijection
650. DFS and topological sorting
651. Tournaments
652. Matching problems (TODO)
653. Four fundamental subspaces
654. WHO list of essential medicines (TODO)
655. why is int i = i allowed in C++?
656. Kakoune cheatsheet
657. Assembly IDE
658. Cohomology is like holism
659. Flows (TODO)
660. Amortized analysis
661. Shelly Kegan: death --- Suicide and rationality (TODO)
662. Sam harris and jordan peterson: Vancouver 1 (TODO)
663. Correctness of binary search
664. readlink -f to access file path
665. rank/select as compress/decompress
666. Remembering Eulerian and Hamiltonian cycles
667. Nice way to loop over an array in reverse
668. Dynamic Programming: Erik Demaine's lectures
669. Accuracy vs precision
670. Why is the gradient covariant?
671. Politicization of science
672. Multi ꙮ cular O: ꙮ / Eye of cthulu
673. You can't measure the one way speed of light
674. Show me the hand strategy
675. Words that can be distinguished from letters if we know the sign of the permutation
676. Easy times don't create weak people, they just allow weak people to survive.
677. Multiplicative weights algorithm (TODO)
678. How to fairly compare groups
679. Bijection from (0, 1) to [0, 1]
680. Rene Girard
681. Noam Chomsky on anarchism (TODO)
682. Slavoj Zizek: Violence
683. Poverty: Who's to blame?
684. Learn Zig in Y minutes
685. The algebraic structure of the 'nearest smaller number' question
686. Why loss of information is terrifying: Checking that a context-free language is regular is undecidable
687. Sciences of the artificial
688. Numbering nodes in a tree
689. Number of vertices in a rooted tree
690. Median minimizes L1 norm
691. LISP quine
692. A slew of order theoretic and graph theoretic results
693. Neko to follow your cursor around
694. Non commuting observables: Light polarization
695. Statement expressions and other GCC C extensions
696. A quick look at impredicativity
697. Data oriented programming in C++
698. Retro glitch
699. SSA as linear typed language
700. Nix weirdness on small machines
701. Autodiff over derivative of integrals
702. Proof of projective duality
703. Preventing the collapse of civilization
704. Violent deaths in ancient societies (TODO)
705. An elementary example of a thing that is not a vector
706. Elementary probability theory (TODO)
707. The handshaking lemma
708. Git for pure mathematicians
709. Mutorch
710. Computing the smith normal form
711. Laziness for C programmers
712. Exact sequence of pointed sets
713. What is a syzygy?
714. Under the spell of Leibniz's dream
715. Normal operators: Decomposition into Hermitian operators
716. Readable pointers
717. The grassmanian, handwavily
718. Lie bracket as linearization of conjugation
719. Computational Origami
720. Katex in duktape
721. Kebab case
722. Localization: Introducing epsilons (TODO)
723. NaN punning: Storing integers in doubles in JavaScript
724. Offline Documentation
725. Using Gurobi
726. osqp: convex optimizer in 6000 LoC
727. stars and bars by generating functions
728. This is not a place of honor
729. Topological proof of infinitude of primes
730. Burnside Theorem
731. The Ise Grand shrine
732. Edward Kmett's list of useful math
733. Cokernel is not sheafy
734. Von neumann: foundations of QM
735. Discrete schild's ladder
736. Derivative of step is dirac delta
737. Extended euclidian algorithm
738. In a PID, all prime ideals are maximal, geometrically
739. Prime numbers as maximal among principal ideals
740. Axiom of Choice and Zorn's Lemma
741. Local ring in terms of invertibility
742. Nullstellensatz for schemes
743. Perspectives on Yoneda
744. Germs, Stalks, Sheaves of differentiable functions
745. Connectedness in terms of continuity
746. Intuition for limits in category theory
747. Finite topologies and DFS numbering
748. Categorical definition of products in painful detail
749. Why is the spectrum of a ring called so?
750. Ergo proxy
751. Satisfied and frustrated equations
752. Combinatorial intuition for Fermat's little theorem
753. An incorrect derivation of special relativity in 1D
754. The geometry and dynamics of magnetic monopoles
755. Sanskrit and Sumerian
756. Writing Cuneiform
757. The code of hammurabi
758. The implicit and inverse function theorem
759. Whalesong hyperbolic space in detail
760. Motivating Djikstra's
761. Intuitions for hyperbolic space
762. Product of compact spaces in compact
763. Hyperbolic groups have solvable word problem
764. Elementary uses of Sheaves in complex analysis
765. Snake lemma
766. Kernel, cokernel, image
767. The commutator subgroup
768. Simplicity of A5 using PSL(2, 5)
769. A5 is not solvable
770. Complex orthogonality in terms of projective geometry
771. Arithmetic sequences, number of integers in a closed interval
772. The arg function, continuity, orientation
773. Odd partitions, unique partitions
774. Continued fractions, mobius transformations
775. Permutations-and-lyndon-factorization
776. Graphs are preorders
777. Parallelisable version of maximum sum subarray
778. Thoughts on implicit heaps
779. Discriminant and Resultant
780. Polynomial root finding using QR decomposition
781. A hacker's guide to numerical analysis
782. Mobius inversion on Incidence Algebras
783. Finite differences and Umbral calculus
784. Permutahedron
785. Lyndon + Christoffel = Convex Hull
786. Geometric proof of e^x >= 1+x, e^(-x) >= 1-x
787. Ranking and Sorting
788. Proof of minkowski convex body theorem
789. Burrows Wheeler
790. Intuitionstic logic as a Heyting algebra
791. Edit distance
792. Evolution of bee colonies (TODO)
793. Best practices for array indexing
794. Algebraic structure for vector clocks
795. Networks are now faster than disks
796. Einstein-de Haas effect
797. Rank-select as adjunction
798. Bounding chains: uniformly sample colorings
799. Coupling from the past
800. Word problems in Russia and America
801. Encoding mathematical hieararchies
802. Learning code by hearing it
803. Your arm can be a spinor
804. Self modifying code for function calls: Look ma, I don't need a stack!
805. Adjunctions as advice
806. Reversible computation as groups on programs
807. Blazing fast math rendering on the web
808. VC dimension
809. Symplectic version of classical mechanics
810. Theorems for free
811. How to reason with half-open intervals
812. How does one build a fusion bomb?
813. Christoffel symbols, geometrically
814. A natural vector space without an explicit basis
815. Cache oblivious B trees
816. Krohn-Rhodes decomposition
817. Proving block matmul using program analysis
818. Why I like algebra over analysis
819. using for cleaner function type typedefs
820. A walkway of lanterns (TODO)
821. Natural transformations
822. The hilarious commentary by dinosaure in OCaml git
823. How to link against MLIR with CMake
824. Energy as triangulaizing state space
825. The cutest way to write semidirect products
826. My Favourite APLisms
827. Proof of chinese remainder theorem on rings
828. monic and epic arrows
829. The geometry of Lagrange multipliers
830. Efficient tree transformations on GPUs (TODO)
831. Things I wish I knew when I was learning APL
832. Every ideal that is maximal wrt. being disjoint from a multiplicative subset is prime
833. Getting started with APL
834. SpaceChem was the best compiler I ever used
835. Mnemonic for Kruskal and Prim
836. Legendre transform
837. Cartesian Trees
838. DFS numbers as a monotone map
839. Self attention? not really
840. Coarse structures
841. Matroids for greedy algorithms (TODO)
842. Grokking Zariski
843. My preferred version of quicksort
844. Geometric proof of Cauchy Schwarz inequality
845. Dataflow analysis using Grobner basis
846. Fenwick trees and orbits
847. Dirichlet inversion
848. Incunabulum for the 21st century: Making the J interpreter compile in 2020
849. An example of a sequence whose successive terms get closer together but isn't Cauchy (does not converge)
850. Krylov subspace method
851. Good reference to the Rete pattern matching algorithm
852. Leapfrog Integration
853. Comparison of forward and reverse mode AD
854. An invitation to homology and cohomology, Part 1 --- Homology
855. An invitation to homology and cohomology, Part 2 --- Cohomology
856. Stuff I learnt in 2019
857. A motivation for p-adic analysis
858. Line of investigation to build physical intuition for semidirect products
859. Topology is really about computation --- part 2
860. Topology is really about computation --- part 1
861. PSLQ algorithm: finding integer relations between reals
862. Geometric characterization of normal subgroups
863. Handy characterization of adding an element into an ideal, proof that maximal ideal is prime
864. Radical ideals, nilpotents, and reduced rings
865. My disenchantment with abstract interpretation
866. Computing equivalent gate sets using grobner bases
867. The janus programming language --- Time reversible computation
868. A = B --- A book about proofs of combinatorial closed forms
869. Generating k bitsets of a given length n:
870. Bondi k-calculus
871. Topology as an object telling us what zero-locus is closed:
872. Vivado toolchain craziness
873. What the hell is a Grobner basis? Ideals as rewrite systems
874. Lie bracket versus torsion
875. Blog post: Weekend paper replication of STOKE, the stochastic superoptimizer
876. Collapsing BlockId, Label, Unique:
877. Spatial partitioning data structures in molecular dynamics
878. Vector: Arthur Whitney and text editors
879. Representing CPS in LLVM using the @coro.* intrinsics
880. Bug in the LLVM code generator: Lowering of MO_Add2 and MO_AddWordC
881. Discrete random distributions with conditioning in 20 lines of haskell
882. Everything you know about word2vec is wrong
883. Hamiltonian monte carlo, leapfrog integrators, and sympletic geometry
884. Small Haskell MCMC implementation
885. The smallest implementation of reverse mode AD (autograd) ever:
886. Timings of passes in GHC, and low hanging fruit in the backend:
887. Varargs in GHC: T7160.hs
888. Debugging debug info in GHC
889. GHC LLVM code generator: Switch to unreachable
890. Concurrency in Haskell
891. Handy list of differential geometry definitions
892. Lazy programs have space leaks, Strict programs have time leaks
893. Presburger arithmetic can represent the Collatz Conjecture
894. Using compactness to argue about covers
895. Japanese Financial Counting system
896. Stephen wolfram's live stream
897. Cleave as a word has some of the most irregular inflections
898. McCune's single axiom for group theory
899. Word2Vec C code implements gradient descent really weirdly
900. Arthur Whitney: dense code
901. How does one work with arrays in a linear language?
902. Linear optimisation is the same as linear feasibility checking
903. Quantum computation without complex numbers
904. Linguistic fun fact: Comparative Illusion
905. Long-form posts:
906. Emacs Cheat Sheet
907. Coq Cheat Sheet
908. Writing Cheat Sheet
909. Latex Cheat Sheet
910. Architecture Cheat Sheet
911. Recipes Cheat Sheet
912. History Cheat Sheet
913. Words Cheat Sheet
914. Clojure Sheat Sheet
915. Big list of quotes
916. Empathy
917. Vim Cheat Sheet
918. Big list of Chess
919. Big list of shitposting
920. Big list of Breakdance
921. Big list of Cardistry
922. Poems to memorize
923. X86 Cheat Sheet
924. Common Lisp Cheat Sheet
925. Agda Cheat Sheet
926. Don't Try
927. Big list of Hacker news
928. Hair in a bun with stick
929. Big list of shuffle dancing
930. Latte Art
931. Big list of tmux
932. Big list of new words
933. Favourite OP1 tutorials
934. Favourite Demoscenes
935. Classical music
936. Blues and Jazz Piano Improv
937. Sheet Music
938. Big List of Artists and Illustrators
939. Big List of Art and Paintings I Enjoy