Discussion of anything and everything relating to chess playing software and machines.
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Nordlandia
Posts: 2821Joined: Fri Sep 25, 2015 9:38 pmLocation: Sortland, Norway
Post by Nordlandia Thu Aug 09, 2018 5:53 am
Hello folks
Set KNNPvKQP + 6-men
i7-5960X 4.5GHz
Samsung 960 Evo.
Amazing isn't it or is it as expected?
As i recall 6-piece syzygy required significantly more time.
[d]8/8/7p/3KNN1k/2p4p/8/3P2p1/8 w - - 0 1
Analysis by Stockfish 010818 64 BMI2:
1.Kc6 g1Q 2.Nxh4 Qa1 3.Nhf3 Qa5 4.Kd6 Qb5 5.Ke6 Qc5 6.Kf5 Qd5 7.Kf4 Qa8 8.Kf5
The position is equal: = (0.00) Depth: 39/28 00:00:01 19355kN, tb=626188
(, 09.08.2018)
Eelco de Groot
Posts: 4565Joined: Sun Mar 12, 2006 2:40 amFull name:
Post by Eelco de Groot Thu Aug 09, 2018 6:26 am
What is the score for the alternative moves, like 1. Ng7+? I suppose that this is easily solved with tablebases especially 7 men but I don't have them installed and without my Stockfish thinks it's a draw... At least in short analysis.
Debugging is twice as hard as writing the code in the first
Nordlandia
Posts: 2821Joined: Fri Sep 25, 2015 9:38 pmLocation: Sortland, Norway
Post by Nordlandia Thu Aug 09, 2018 6:33 am
It's at -10 a clear defeat.
Eelco de Groot
Posts: 4565Joined: Sun Mar 12, 2006 2:40 amFull name:
Post by Eelco de Groot Thu Aug 09, 2018 11:50 am
Nordlandia wrote: ↑ Thu Aug 09, 2018 6:33 am
It's at -10 a clear defeat.
Doesn't that mean though that Black can't exchange to a winning KNNPvKQP situation or a winning 6 men. That would be a tablebase win. Assuming the g pawn is promoted to a Queen, probably the c pawn, White's d pawn and at least one of the h pawns is still on board, but Black can't afford to promote. I'm not sure because without tablebases Stockfish will exchange to a drawn Q against NN. Can Black achieve KNNvKQPP then you would expect another promotion and easy win. So I'm not 100% sure your -10 for White is not a fortress. But you left it running I suppose for just a few minutes...
Debugging is twice as hard as writing the code in the first
Jouni
Posts: 3286Joined: Wed Mar 08, 2006 8:15 pm
Post by Jouni Thu Aug 09, 2018 12:22 pm
Stunning! But I quess 7 piece benefit is very small in real play. How has the first preliminary numbers?
Jouni
Eelco de Groot
Posts: 4565Joined: Sun Mar 12, 2006 2:40 amFull name:
Post by Eelco de Groot Thu Aug 09, 2018 12:28 pm
Without tablebases, not even 5 men:28/50 0:01 -2.66 1.Ng7+ Kg5 2.Nf3+ Kg4 3.Ke4 h3 4.Nf5 g1Q
Debugging is twice as hard as writing the code in the first
MikeB
Posts: 4889Joined: Thu Mar 09, 2006 6:34 amLocation: Pen Argyl, Pennsylvania
Post by MikeB Fri Aug 10, 2018 6:23 am
With 7 man syzygy, one may also get endings like this - here black takes white to the 50th ply, but has to sacrifice the Q on the 50th move to avoid mate , and then mate shortly follows. Quite a King walk.
