tromp/ChessPositionRanking on Hacker News

…testing), not valid chess games (based on estimating branching factors for very long games). [0] https://github.com/tromp/ChessPositionRanking

comment by LegionMammal978 · 2026-01-28 · in How many chess games are possible?

…one can make (until the encoding just becomes an index in the set of all unique db positions). [1] https://github.com/tromp/ChessPositionRanking

comment by tromp · 2026-01-09 · in How to store a chess position in 26 bytes (2022)

…> By checking all approximately 8.7x10^45 reachable chess positions? That's a large overestimate. https://github.com/tromp/ChessPositionRanking accurately estimates the number of legal chess positions at ~4.8x10^44.

comment by tromp · 2025-09-26 · in No reachable chess position with more than 218 moves

…to one side's advantage, as is clear from sampling a few dozen random legal positions. [1] https://github.com/tromp/ChessPositionRanking

comment by tromp · 2024-12-09 · in How God Plays Chess (2018)

…for distinguishing their quality, since usually one side already has an overwhelming advantage. [1] https://github.com/tromp/ChessPositionRanking

comment by tromp · 2024-11-21 · in OK, I can partly explain the LLM chess weirdness now

…positions that might or might not be legal. [1] https://github.com/peterosterlund2/texel [2] https://github.com/tromp/ChessPositionRanking

comment by tromp · 2024-05-17 · in Finding Mona Lisa in the Game of Life (2020)

…illegal positions like https://chess.maxmcd.com/rnbqkbnr/qqqqqqqq/8/8/8/8/QQQQQQQQ/... as well. [1] https://github.com/tromp/ChessPositionRanking

comment by tromp · 2024-05-14 · in Static Chess

…must be reachable by a sequence of legal moves from the starting position, however dumb), see https://github.com/tromp/ChessPositionRanking . You can probably filter their sample by number of pieces to gain pretty accurate estimations for…

comment by Sesse__ · 2024-04-03 · in Los Alamos Chess

…over legal moves. Related: accurately estimating the number of legal positions of chess [1]. [1] https://github.com/tromp/ChessPositionRanking

comment by tromp · 2024-03-15 · in Compressing chess moves for fun and profit

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Chess Position Ranking

story by bebop404 · 2023-11-06 · 0 comments

…like that pawns can't be on their own back row. That is significantly harder. It looks to me like https://github.com/tromp/ChessPositionRanking has resolved these sorts of issues, but I haven't dug into exactly how.

comment by HALtheWise · 2023-09-15 · in How to store a chess position in 26 bytes using bit-level magic (2022)

…in log_2(8726713169886222032347729969256422370854716254) ~ 152.6 bits ~ 19.1 bytes using rankings: https://github.com/tromp/ChessPositionRanking But the major point of this project is to allow for random sampling of positions with a decent…

comment by tromp · 2023-09-15 · in How to store a chess position in 26 bytes using bit-level magic (2022)

…how many are legal, and thus obtain an accurate estimate of 4.8 * 10^44 legal chess positions. [1] https://github.com/tromp/ChessPositionRanking/blob/main/src/... [2] https://github.com/tromp/ChessPositionRanking

comment by tromp · 2023-08-23 · in Permutation iteration and random access

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Accurately estimating the number of legal chess positions

story by ca98am79 · 2022-12-23 · 1 comment

…[3] https://tromp.github.io/go.html [4] https://tromp.github.io/go/legal.html [5] https://github.com/tromp/ChessPositionRanking#readme

comment by tromp · 2022-11-18 · in Ask HN: What is the most impactful thing you've built?

…build a tree with all legal chess positions, it would have approximately 4.8x10^44 of them [1]. [1] https://github.com/tromp/ChessPositionRanking

comment by tromp · 2022-07-20 · in Magnus Carlsen to give up World Championship title

…though.) http://talkchess.com/forum3/viewtopic.php?f=7&t=77685&sid=e3... Practically speaking, https://github.com/tromp/ChessPositionRanking gives a number between 0 and approx. 8.7 * 10^45 for any legal position, so it's only a couple of…

comment by Sesse__ · 2022-07-03 · in How to build a chess engine

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Chess Position Ranking

story by Nydhal · 2022-05-24 · 0 comments

…their legality [4] allowed us to estimate the number of legal chess positions as ~ 4.8 * 10^44. [1] https://github.com/tromp/ChessPositionRanking/blob/main/src/... [2] https://hackage.haskell.org/package/simple-enumeration-0.2/d... [3]…

comment by tromp · 2022-05-20 · in A maximally-dense encoding for n-choose-k (2013)

…number of legal chess positions has now been estimated with 2 digits of accuracy as ~ 4.8 x 10^44: https://github.com/tromp/ChessPositionRanking For the game of Go, we know all 171 digits of the number: https://tromp.github.io/go/legal.htm

comment by tromp · 2022-04-30 · in Ask HN: Teach me something new

…positions, in Haskell because of the ease of building powerful abstractions like a Ranking [2]. [1] https://github.com/tromp/ChessPositionRanking [2] https://github.com/tromp/ChessPositionRanking/blob/main/src/...

comment by tromp · 2022-02-26 · in Ask HN: Why are you programming your hobby projects in a niche language?

Github user @Ananas1729 (Ben Jones) found another at https://github.com/tromp/ChessPositionRanking/issues/243

comment by tromp · 2021-09-23 · in The number of legal chess positions estimated at 4.5x10^44 – proof games wanted

And yet another at https://github.com/tromp/ChessPositionRanking/issues/186

comment by tromp · 2021-09-22 · in The number of legal chess positions estimated at 4.5x10^44 – proof games wanted

And another at https://github.com/tromp/ChessPositionRanking/issues/111

comment by tromp · 2021-09-19 · in The number of legal chess positions estimated at 4.5x10^44 – proof games wanted

And another at https://github.com/tromp/ChessPositionRanking/issues/476#iss...

comment by tromp · 2021-09-18 · in The number of legal chess positions estimated at 4.5x10^44 – proof games wanted

…use IO (), while the other approximately thousand lines of code have nothing to do with IO (). [1] https://github.com/tromp/ChessPositionRanking

comment by tromp · 2021-09-14 · in Functional programming is not popular because it is weird (2016)

Peter Osterland found yet another misclassification in https://github.com/tromp/ChessPositionRanking/issues/824

comment by tromp · 2021-09-12 · in The number of legal chess positions estimated at 4.5x10^44 – proof games wanted

…the two misjudgements cancel out and the original 538 count currently still stands. Lovely:-) [1] https://github.com/tromp/ChessPositionRanking/issues/794

comment by tromp · 2021-09-08 · in The number of legal chess positions estimated at 4.5x10^44 – proof games wanted

A misclassified issue was found by Github user 1pab42 at https://github.com/tromp/ChessPositionRanking/issues/878 That changes the prospective number of legal positions to 539...

comment by tromp · 2021-09-06 · in The number of legal chess positions estimated at 4.5x10^44 – proof games wanted

…issue, I was surprised to not find the position among the open issues. In fact it was closed as https://github.com/tromp/ChessPositionRanking/issues/915 So I had classified it correctly, but only AFTER making the diagrams for the 1k…

comment by tromp · 2021-09-05 · in The number of legal chess positions estimated at 4.5x10^44 – proof games wanted

…the en-passant positions in the 919-93 positions not from the smaller 1k sample, such as this one: https://github.com/tromp/ChessPositionRanking/issues/916 I'll have to make some changes to my README. Meanwhile, congratulations on spotting…

comment by tromp · 2021-09-05 · in The number of legal chess positions estimated at 4.5x10^44 – proof games wanted

…let you draw a random sample to determine the fraction of legal ones, as needed for estimation. [1] https://github.com/tromp/ChessPositionRanking/blob/main/src/... [2] https://github.com/tromp/ChessPositionRanking/blob/main/src/... [3]…

comment by tromp · 2021-09-05 · in The number of legal chess positions estimated at 4.5x10^44 – proof games wanted

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The number of legal chess positions estimated at 4.5x10^44 – proof games wanted

story by tromp · 2021-09-05 · 97 comments

I wrote a nontrivial Haskell application this year [1] and use exactly 0 language extensions. [1] https://github.com/tromp/ChessPositionRanking/tree/main/src/...

comment by tromp · 2021-08-31 · in Brooks, Wirth and Go

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Help improve the estimated number of legal chess positions

story by tromp · 2021-08-15 · 2 comments

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The number of legal chess positions is roughly 4e44

story by tromp · 2021-08-08 · 0 comments