271
π in Other Universes
How the value of π depends on the definition of distance.
Topics /
Math & Algorithms
The most popular blog posts about math & algorithms on Hacker News. 2,391 posts.
272
Fastest branchless binary search
Fastest general and simple binary search C++ implementation
273
State machines are wonderful tools
I love when my current problem can be solved with a state machine. They’re fun to design and implement, and I have high confidence about correctness. They tend to:
274
275
Benoit Mandelbrot, RIP
Nothing in the news media yet, but many folks on Twitter and colleague Nassim Taleb are reporting that the father of fractal geometry is dead at age 85. We’re n
276
Introduction to A* (1997)
Movement for a single object seems easy. Pathfinding is complex. Why bother with pathfinding? Consider the following situation:
277
278
A digestion of the Jacobian conjecture counterexample
The notorious Jacobian conjecture can be formulated concretely over the complex numbers as follows. Conjecture 1 (Jacobian Conjecture) Let $latex {F:{\bf C}^n \rightarrow {\bf C}^n}&fg=000000$ …
279
How random can you be?
Compare top same day payout casinos in Canada with verified withdrawal speeds, bonus offers, and player ratings for 2026.
280
Calculus Is Deeply Irrational
You’re lying on a beautiful beach when you feel a tap on your shoulder, and suddenly you’re not at the beach at all — you’re in a classroom. The student who woke you looks apologe…
281
Divisibility by 7 is a Walk on a Graph (2009)
Mathematics, applications of mathematics to life in general, and my life as a mathematician.
282
An Overview of Cryptography
Free, evolving crypto tutorial since 1999!
283
Learning from Scratch by Thinking Fast and Slow
Reinforcement Learning
284
285
Forecasts need to have error bars
Richard Rosenfeld in the most recent Criminologist published a piece about forecasting national level crime rates. People complain about the FBI releasing crime stats a year late, academics are wor…
286
Seven sins of numerical linear algebra
In numerical linear algebra we are concerned with solving linear algebra problems accurately and efficiently and understanding the sensitivity of the problems to perturbations. We describe seven si…
287
The Color of Infinite Temperature
This is the color of something infinitely hot. Of course you’d instantly be fried by gamma rays of arbitrarily high frequency, but this would be its spectrum in the visible range. This…
288
Modes, Medians and Means: A Unifying Perspective
Introduction / Warning Link to heading Any traditional introductory statistics course will teach students the definitions of modes, medians and means. But, because introductory courses can’t assume that students have much mathematical maturity, the close relationship between these three summary statistics can’t be…
289
Conway's Game of Life, in real life
When life gives you switches...
290
Folks, we have the best π
And some novel ideas for bicycle wheel design.
291
Common statistical tests are linear models
By Jonas Kristoffer Lindeløv ( blog , profile ). Last updated: 28 June, 2019 (See changelog ). Check out the Python version and the Twitter summary .
292
293
B-trees in Factorio
learning about B-Trees...in factorio
294
Alonzo Church: Architect of computer intelligence
The man who gave us the solution to the Entscheidungsproblem
295
The Paxos Algorithm, or How to Win a Turing Award
The lectures assume no prior knowledge of the Paxos consensus algorithm or of TLA+, the language in which the specifications are written. In fact, the lectures constitute a crash course on TLA+. If you're interested just in the algorithm, you will probably find the specs annoying and will try to read only the…
296
Elliptic Curve Cryptography for Beginners
A description of ECC without using advanced math
297
298
How to Fold a Julia Fractal
A tale of numbers that like to turn: a different look at complex numbers and the strange things they do.
299
300
Words that do Handstands
The other day I ordered a book on art history from Amazon… which reminded me of the movie Angels and Demons , which reminded me of ambigrams. Ambigrams are those stylized words that look the same when you turn them upside down. Here is the classic, by John Langdon .