20
votes
Accepted
What is the status for EIGHT piece endgame tablebases?
Marc Bourzutschky's Google Drive with progress information
Bourzutschky's first email regarding his progress
Bourzutschky's second email regarding his progress
Kirill Kryukov's Endgame Tablebase ...
- 780
19
votes
Accepted
Do Stockfish and the tablebase work together or independently?
play the game until six pieces
Stockfish doesn't do that, that's not what tablebase is for. Briefly, tablebase boosts engine search well before six-men position reached on the board.
Let's do an ...
- 22.7k
19
votes
Accepted
How does Syzygy store its information?
Since there is no single comprehensive publication this is based on the probing code, the generator and various explanations from Ronald de Man (the author of the generator).
When probing pretty much ...
- 457
17
votes
Accepted
Are there attempts at creating practical endgame tablebases?
There is a contradiction in terms in "only" generating practical endgame tablebases. We have to understand how tablebases are generated to see why.
Tablebases are generated by working backwards from ...
- 5,030
16
votes
What do DTM, DTZ, DTC, DTR, DTZ50, and DTZR mean?
In various endgame tablebases, the terms mean as follows:
Depth to Mate. For each position that is represented, 'DTM' indicates the theoretical value, and the number of winner's moves to 'Mate' if ...
- 3,917
13
votes
What is the status for EIGHT piece endgame tablebases?
We are still far away from the solution. Estimates for the size of the completed tablebase are around 10 Petabytes. Compare that to the 140 Terabyte hard drive (later trimmed down to 18TB in the ...
- 379
12
votes
Accepted
What percentage of the time does White win in the Lomonosov tablebase?
As I do not have access to the full Lomosonov tablebases, here is an answer based on the Syzygy tablebases, which are available online in machine-readable format. I interpret your question as "...
- 901
11
votes
Does the Lomonosov Tablebase (and others) include extra material positions such as KQQvKQQQ?
The Lomonossov tablebases include all 7-man positions with the exception of 6 pieces vs lone king.
Most material distributions you consider "ridiculous" are in fact required to evaluate "interesting" ...
- 692
11
votes
Accepted
How far from solving chess are we?
Currently most of the 7-piece Lomonosov tablebases have been created. the only ones that weren't, were the K vs. K + 5 pieces. Those took about 6 months using the Lomonosov supercomputer.
Based on ...
- 4,291
11
votes
Estimation of "God's Elo"
I'm arguing below that it is logically problematic to even define such a thing.
The ELO of the strongest computers is really defined only relative to a ladder of weaker computers, starting from the ...
- 1,912
10
votes
Accepted
Tablebases say this position is drawn, but Stockfish disagrees-What does that mean?
If the tablebase says that it's a draw with optimal play from both sides, then you can always ignore whatever Stockfish or any other engine says. The tablebase knows the objective evaluation for any ...
- 19.9k
9
votes
Accepted
How is it possible that the Lomonosov-endgame-tablebase from 2012 still is the most powerful tablebase?
I am a developer currently working on software to compute endgame tablebases. The real bottleneck with calculating positions is not memory per se but the working memory and computing cycles needed to ...
- 206
9
votes
Accepted
How can I download Syzygy tablebases efficiently?
I found out wget supports mirror site listings, so I used
wget --mirror --no-parent --no-directories -e robots=off http://tablebase.sesse.net/syzygy/3-4-5/
It might take a few tries to download all ...
- 4,069
9
votes
Accepted
Are Nalimov tables still being built?
Certainly there is work on 8-man tablebases.
One source of information on this is from the Chess Endgame Study Association here This article describes pawnless ending work.
It is simpler to start with ...
- 5,206
7
votes
Longest way to mate with 1 queen against 4 queens
This max-DTZ position is mate in 8, but probably also a dead-end because it seems hard to improve starting here.
[FEN "7q/4q1q1/8/8/3q2Q1/1K6/8/1k6 w - - 0 1"]
1. Qf5+ Qde4 2. Qf1+ Qe1 3. Qd3+ Ka1 4....
- 457
7
votes
How far from solving chess are we?
Not only are we far from solving chess, in all likelihood chess will never be solved. There are more possible positions in chess than atoms in the known universe, so not only would in take forever (...
- 301
6
votes
Longest way to mate with 1 queen against 4 queens
The best I could come up with is 7 moves, I don't believe it could take much longer, because with 4 queens there's not as much freedom as with 2, I cannot put black king in the middle of the board ...
- 1,736
6
votes
What is the status for seven man end game table bases?
7-men Syzygy tables are available for download:
ftp://ftp.chessdb.cn/pub/syzygy/
Mirrors:
http://tablebase.sesse.net/syzygy/
https://tablebase.lichess.ovh/tables/standard/
As of August 2018, only ...
- 151
6
votes
Is there an online database for the endgame KRPPKRP?
All of the Syzygy tablebases are available here: https://syzygy-tables.info/
These cover all endgames up to 7-man, and provide WDL (win-draw-loss) and DTZ (distance to zeroing move) data. Syzygy ...
- 1,689
6
votes
Accepted
Does the Lomonosov Tablebase (and others) include extra material positions such as KQQvKQQQ?
The Lomonosov Endgame Tablebase supports 7 pieces. That means it has all the positions you describe in your question. Otherwise, it's not a tablebase by definition.
The "ridiculous" positions you ...
- 22.7k
6
votes
Accepted
Is it possible to get DTM of a position from sygyzy tables?
No. It's not possible. People use Gaviota tablebase if they want to do DTM or the old Nalimov.
Syzygy tablebase is the most popular tablebase algorithm because it doesn't do DTM, better compression. ...
- 22.7k
6
votes
Has Explainable AI been applied to the endgame tablebases?
In short: yes. Although I don't have an overlook on current research. But already with the endgame KR/K, which is as much the drosophila of tablebases as chess is for KI, was handled this way, and for ...
- 17.3k
6
votes
Why hasn't any new endgame theory been developed from the endgame tablebases?
Endgame complexity scales super-exponentially with the number of pieces. This is why each successive N+1-piece tablebase takes so much more computing power than N-piece tablebase.
This isn't merely a ...
- 7,594
5
votes
How far from solving chess are we?
We are very very far from solving chess. We would need a 32 man tablebase for that. Currently, we have a 7 man tablebase. Each increase of 1 step, requires exponentially more computing power and ...
- 227
5
votes
Are there attempts at creating practical endgame tablebases?
It is difficult to define the exact boundary of practical vs. impractical. However, you can define this for yourself.
See this project
You can decide what you want to generate like:
rtbgen ...
- 5,206
5
votes
Accepted
What is the longest tablebase win that includes draw rules?
Unfortunately looking for the longest mates on Kyrill Kryukov and checking with Syzygy won't give you the answer. The mate lengths ignoring the 50 move rule don't correspond with the mate lengths when ...
- 482
5
votes
The state of chess when it becomes solved (or nearly solved)
For the average player, not much changes.
The problem is: Even if you can get to that exact position 24 moves deep in an actual game, and even if you know that 25.dxc6 leads to mate in 105, you have ...
- 20.3k
5
votes
4
votes
Is there an online database for the endgame KRPPKRP?
The 7-men databases from Lomonosov are available for free via their Android app.
I've analyzed the traffic between the app and server a while ago, and discovered that it's easy to 'fake' your own ...
- 25k
4
votes
Is there a freely available online 7 piece Endgame tablebase?
https://syzygy-tables.info/ allows to look up 7-men endgame positions. It does not give DTM information for 6- and 7-men endgames, only DTZ50+. On one hand, it is compliant with 50-move rule, OTOH, ...
- 151
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