KNNN vs K : how come Stockfish cannot find the mate in 17?

[Rebel]

To make a long story short, I have posted an entry on the subject on my blog. Am I missing something here?

Stockfish seems to be unable to find this mate in 17 and alternates between different results even though its search deep enough to have seen the mate in 17!

My blog entry:

https://endormitoire.wordpress.com/2018 ... 3-knights/

P.S. Please reply here (not on my blog) !!

tia

[D]4k3/8/8/8/8/8/8/4KNNN w - - 0 1

ProDeo mate in 19 after 2 hours.

Code: Select all

 02:01:02  24.01  M 19  1.Nhg3 Ke7 2.Kd2 Ke6 3.Nf3 Kd7 4.Ne5

[CMCanavessi]

Shredder 13 (not deep), 1 thread of course, 4 gb hash

info depth 41 seldepth 43 time 308802 score mate 17 lowerbound nodes 1226764439 nps 3972657 hashfull 214 pv g1f3

308 seconds = 5 minutes 8 seconds, not bad


Houdini 6.03 can't get lower than mate in 18 with 1 thread after running for a while (depth 63).

[Maarten Claessens]

To make a long story short, I have posted an entry on the subject on my blog. Am I missing something here?

Stockfish seems to be unable to find this mate in 17 and alternates between different results even though its search deep enough to have seen the mate in 17!

My blog entry:

https://endormitoire.wordpress.com/2018 ... 3-knights/

P.S. Please reply here (not on my blog) !!

tia

[D]4k3/8/8/8/8/8/8/4KNNN w - - 0 1

ProDeo mate in 19 after 2 hours.

Code: Select all

 02:01:02  24.01  M 19  1.Nhg3 Ke7 2.Kd2 Ke6 3.Nf3 Kd7 4.Ne5

WaDuuttie mate in 18 just under 5 minutes 30 seconds:

Code: Select all

  39	05:29	1,100,671,466	3,341,849	+M18	h1f2 e8d7 f1g3 d7c6 e1e2 c6c7 f2e4 c7d7 e2d3 d7e8 d3c4 e8f8 g1f3 f8f7 c4d5 f7e8 g3f5 e8d7 e4f6 d7c7 d5c5 c7b7 c5b5 b7b8 b5b6 b8a8 f3e5 a8b8 f5d4 b8c8 d4b5 c8d8 e5c6 d8c8 b5d6

And still mate in 18 after 2 and a half hour:

Code: Select all

  48	2:25:18	30,749,676,168	4,343,561	+M18	h1f2 e8d7 f1g3 d7c6 e1e2 c6c7 f2e4 c7d7 e2d3 d7e8 d3c4 e8f7 g1f3 f7e6 f3g5 e6e5 c4c5 e5f4 c5d4 f4g4 d4e3 g4h4 g5e6 h4g4 e3e2 g4h3 e2f3 h3h2 e6f4 h2g1 e4f6 g1h2 f6g4 h2g1 f4e2

[sovaz1997]

Stockfish 9
Hash=4096
Intel Core i7-860 (with HT)
7 threads

149 seconds:

Code: Select all

info depth 68 seldepth 36 multipv 1 score mate 17 nodes 2536321387 nps 16942241 hashfull 317 tbhits 0 time 149704 pv e1d2 e8d7 f1e3 d7d6 g1f3 d6c6 h1g3 c6c7 d2c3 c7d7 g3e4 d7e7 f3e5 e7e8 c3c4 e8d8 e3f5 d8c8 c4b5 c8c7 e4f6 c7b7 f6d5 b7c8 b5a6 c8d8 f5g7 d8c8 g7e6 c8b8 e5c6 b8c8 d5b6

[pilgrimdan]

To make a long story short, I have posted an entry on the subject on my blog. Am I missing something here?

Stockfish seems to be unable to find this mate in 17 and alternates between different results even though its search deep enough to have seen the mate in 17!

My blog entry:

https://endormitoire.wordpress.com/2018 ... 3-knights/

P.S. Please reply here (not on my blog) !!

tia

[D]4k3/8/8/8/8/8/8/4KNNN w - - 0 1

[D]4kn2/8/8/8/8/8/8/4KNNN w - - 0 1?

is this a mate for white ...

[zullil]

To make a long story short, I have posted an entry on the subject on my blog. Am I missing something here?

Stockfish seems to be unable to find this mate in 17 and alternates between different results even though its search deep enough to have seen the mate in 17!

My blog entry:

https://endormitoire.wordpress.com/2018 ... 3-knights/

P.S. Please reply here (not on my blog) !!

tia

[D]4k3/8/8/8/8/8/8/4KNNN w - - 0 1

[D]4kn2/8/8/8/8/8/8/4KNNN w - - 0 1?

is this a mate for white ...

Yes, in 33 moves.

[pilgrimdan]

To make a long story short, I have posted an entry on the subject on my blog. Am I missing something here?

Stockfish seems to be unable to find this mate in 17 and alternates between different results even though its search deep enough to have seen the mate in 17!

My blog entry:

https://endormitoire.wordpress.com/2018 ... 3-knights/

P.S. Please reply here (not on my blog) !!

tia

[D]4k3/8/8/8/8/8/8/4KNNN w - - 0 1

[D]4kn2/8/8/8/8/8/8/4KNNN w - - 0 1?

is this a mate for white ...

Yes, in 33 moves.

...

[syzygy]

[D]4kn2/8/8/8/8/8/8/4KNNN w - - 0 1?

is this a mate for white ...

Yes, in 33 moves.

All moves win:

Code: Select all

info depth 1 seldepth 1 multipv 1 score mate 33 nodes 0 nps 0 tbhits 13 time 1 pv f1e3 f8e6 g1e2 e6c5 h1f2 c5b3 f2d3 e8d7 e1f2 b3d2 e2c3 d7c6 f2g3 c6d7 g3g4 d7e6 g4f4 e6d7 f4f5 d2f3 c3e4 f3d4 f5e5 d4f3 e5d5 f3h4 e4c5 d7e7 d3e5 e7f6 d5e4 f6e7 e4f4 e7d6 c5d3 d6c7 f4g5 c7b7 e3d5 h4f3 e5f3 b7c6 d5c3 c6d6 f3d4 d6c7 g5f6 c7d6 f6f7 d6d7 c3b5 d7c8 d3c5 c8d8 d4c2 d8c8 f7e7 c8b8 e7d7 b8a8 c2b4 a8b8 b4c6 b8a8 b5c7
info depth 1 seldepth 1 multipv 2 score mate 33 nodes 0 nps 0 tbhits 13 time 1 pv g1e2 f8e6 f1e3 e6c5 h1f2 c5b3 f2d3 e8d7 e1f2 b3d2 e2c3 d7c6 f2g3 c6d7 g3g4 d7e6 g4f4 e6d7 f4f5 d2f3 c3e4 f3d4 f5e5 d4f3 e5d5 f3h4 e4c5 d7e7 d3e5 e7f6 d5e4 f6e7 e4f4 e7d6 c5d3 d6c7 f4g5 c7b7 e3d5 h4f3 e5f3 b7c6 d5c3 c6d6 f3d4 d6c7 g5f6 c7d6 f6f7 d6d7 c3b5 d7c8 d3c5 c8d8 d4c2 d8c8 f7e7 c8b8 e7d7 b8a8 c2b4 a8b8 b4c6 b8a8 b5c7
info depth 1 seldepth 1 multipv 3 score mate 33 nodes 0 nps 0 tbhits 13 time 1 pv g1f3 f8e6 f1e3 e6f4 h1f2 e8e7 f2e4 e7d7 e1d1 f4d3 d1d2 d3f4 d2c3 f4e2 c3b4 e2f4 b4c5 f4e2 e3d5 d7e6 e4d6 e2g3 d5f4 e6e7 c5d5 e7f6 d5c6 g3f5 d6e4 f6e7 c6c7 e7e8 f3g5 e8f8 c7d8 f8g7 d8d7 f5h4 d7e8 h4g6 f4e6 g7h6 g5f3 g6h4 f3h4 h6h5 h4g2 h5g4 e6d4 g4h5 g2e3 h5h4 e8f7 h4h3 d4f5 h3h2 e4f2 h2g1 f2g4 g1h1 f5d4 h1g1 d4f3 g1h1 g4f2
info depth 1 seldepth 1 multipv 4 score mate 33 nodes 0 nps 0 tbhits 13 time 1 pv h1f2 f8e6 g1f3 e8e7 f2e4 e6f4 f1e3 e7d7 e1d1 f4d3 d1d2 d3f4 d2c3 f4e2 c3b4 e2f4 b4c5 f4e2 e3d5 d7e6 e4d6 e2g3 d5f4 e6e7 c5d5 e7f6 d5c6 g3f5 d6e4 f6e7 c6c7 e7e8 f3g5 e8f8 c7d8 f8g7 d8d7 f5h4 d7e8 h4g6 f4e6 g7h6 g5f3 g6h4 f3h4 h6h5 h4g2 h5g4 e6d4 g4h5 g2e3 h5h4 e8f7 h4h3 d4f5 h3h2 e4f2 h2g1 f2g4 g1h1 f5d4 h1g1 d4f3 g1h1 g4f2
info depth 1 seldepth 1 multipv 5 score mate 33 nodes 0 nps 0 tbhits 13 time 1 pv h1g3 f8e6 g1e2 e6c5 f1e3 e8d7 e1d2 d7d6 d2c3 c5e6 c3c4 e6g5 e2f4 g5f3 e3f5 d6e5 f4d3 e5e6 c4c5 f3d2 f5d4 e6f6 c5d5 f6g5 d5e6 g5g4 g3f5 g4h5 f5e3 h5g5 e6f7 d2e4 d4f3 g5h6 f7e7 e4g5 f3d2 g5h3 e7f6 h3g5 d3f4 g5h7 f6f7 h6g5 f4e6 g5h4 d2e4 h4h5 f7g7 h7f8 g7f8 h5h4 e6g7 h4h3 g7f5 h3h2 e4f2 h2g1 f2g4 g1h1 f5d4 h1g1 d4f3 g1h1 g4f2
info depth 1 seldepth 1 multipv 6 score mate 33 nodes 0 nps 0 tbhits 13 time 1 pv e1d2 f8e6 f1e3 e6g5 h1f2 e8d7 g1e2 g5f3 d2d3 f3g5 f2g4 d7d6 e2f4 d6c5 e3f5 g5f7 g4f6 f7e5 d3e4 e5f7 f4e6 c5c4 f5e3 c4b4 e4d5 b4c3 e3g4 c3d2 d5c6 d2d1 c6d7 d1c1 d7e7 f7h8 g4e5 c1b1 e6d4 b1c1 f6e4 c1d1 e7d6 d1c1 d6c5 c1d1 e5f3 h8g6 c5b4 g6h4 e4c3 d1c1 d4b3 c1b2 f3d4 h4f3 d4f3 b2c2 f3e1 c2b2 b4c4 b2a3 b3c1 a3b2 c1d3 b2a1 e1c2
info depth 1 seldepth 1 multipv 7 score mate 33 nodes 0 nps 0 tbhits 13 time 1 pv e1e2 f8e6 f1e3 e6c5 h1f2 e8d7 g1f3 d7d6 f2h3 c5b3 h3f4 b3a5 e3f5 d6c5 f3d2 a5c4 d2e4 c5c6 e2d3 c4e5 d3c3 e5f3 e4f6 f3e5 f4e6 c6b6 f5e7 b6a5 f6e4 a5a6 e4d6 a6b6 c3b3 e5d3 b3c4 d3e5 c4c3 e5f3 c3b4 f3e5 d6c8 b6b7 b4b5 e5f7 b5a5 f7e5 c8d6 b7a7 e6d4 a7b8 d4b5 b8a8 a5b6 a8b8 b6a6 b8a8 b5c7 a8b8 c7d5 b8a8 d5b6 a8b8 d6b5 e5d3 e7c6
info depth 1 seldepth 1 multipv 8 score mate 34 nodes 0 nps 0 tbhits 13 time 1 pv f1d2 f8e6 h1g3 e6g5 g1e2 g5e6 g3e4 e8d7 d2f3 d7c6 e2c3 c6d7 f3e5 d7d8 e1e2 e6c7 e4c5 d8e7 c3e4 c7d5 e5c6 e7f8 e4d6 f8g7 e2f2 g7f6 f2f3 f6g6 c5d7 g6h5 c6d4 h5h6 d4e6 h6g6 f3g3 d5e3 g3f4 e3d5 f4f3 d5c3 f3g4 c3d5 e6f8 g6g7 g4g5 d5c7 g5h5 c7d5 f8e6 g7h7 d6e4 h7h8 h5h6 d5f6 d7e5 f6g8 h6g5 g8f6 g5f6 h8h7 f6g5 h7h8 g5f5 h8g8 e4f6 g8h8 e5g6
info depth 1 seldepth 1 multipv 9 score mate 34 nodes 0 nps 0 tbhits 13 time 1 pv f1g3 f8e6 h1f2 e8d7 g1f3 d7c6 f2d3 c6b5 f3e5 e6d4 g3e4 d4c6 e4c3 b5b6 e5c4 b6c7 e1d2 c6e7 d3e5 c7d8 d2d3 e7c8 d3d4 c8e7 c4e3 e7g8 c3e4 d8e7 e5g4 e7e6 e4g5 e6d7 e3f5 d7c6 g4e5 c6b5 g5e4 b5b6 d4c4 b6c7 c4c5 c7d8 e4d6 d8c7 f5d4 g8e7 d4e6 c7b8 c5b4 b8a7 b4a5 a7a8 e6c7 a8a7 c7b5 a7b8 a5a6 b8a8 d6c4 e7d5 e5c6 d5b4 c6b4 a8b8 b4c6 b8c8 c4b6
info depth 1 seldepth 1 multipv 10 score mate 34 nodes 0 nps 0 tbhits 13 time 1 pv g1h3 f8e6 h1g3 e6c5 f1e3 e8d7 e1d2 d7d6 d2c3 c5e6 h3f2 e6f4 c3d4 f4e6 d4c4 e6f4 f2g4 d6e7 g3e4 e7d7 e4g5 f4e6 g4e5 d7d6 g5f7 d6e7 e3d5 e7f8 f7d6 f8g7 d6f5 g7f8 d5f6 e6f4 f6g4 f4h5 g4h6 h5f6 c4b5 f6e4 e5g6 f8e8 b5c6 e8d8 h6g4 e4d2 g4e5 d2e4 f5d4 e4g5 c6b7 g5f7 e5f7 d8d7 b7b8 d7e8 f7e5 e8d8 d4c2 d8e8 c2e3 e8d8 e3g4 d8e8 g4f6 e8d8 e5c6
info depth 1 seldepth 1 multipv 11 score mate 34 nodes 0 nps 0 tbhits 13 time 1 pv e1d1 f8e6 f1e3 e6f4 h1f2 e8d7 f2e4 f4d3 g1f3 d3b4 d1c1 b4d3 c1d2 d3f4 d2c3 f4e2 c3b4 e2f4 b4c5 f4e2 e3d5 d7e6 e4d6 e2g3 d5f4 e6e7 c5d5 e7f6 d5c6 g3f5 d6e4 f6e7 c6c7 e7e8 f3g5 e8f8 c7d8 f8g7 d8d7 f5h4 d7e8 h4g6 f4e6 g7h6 g5f3 g6h4 f3h4 h6h5 h4g2 h5g4 e6d4 g4h5 g2e3 h5h4 e8f7 h4h3 d4f5 h3h2 e4f2 h2g1 f2g4 g1h1 f5d4 h1g1 d4f3 g1h1 g4f2
info depth 1 seldepth 1 multipv 12 score mate 34 nodes 0 nps 0 tbhits 13 time 1 pv e1f2 f8e6 h1g3 e8d7 g1e2 e6c5 f1d2 c5e6 f2e3 d7d6 g3e4 d6e7 d2b3 e6f8 e3d4 f8d7 e2f4 d7f6 e4d2 f6g4 b3c5 g4f6 d2c4 e7e8 c4e5 e8e7 f4g6 e7d6 g6h4 f6h5 h4f5 d6c7 c5e4 h5f4 d4c5 f4h5 f5d4 h5f4 e4g5 c7b7 c5d6 f4g2 e5c4 g2e1 g5e4 e1d3 d6d7 d3b4 e4c5 b7b8 d7d8 b8a8 c4b6 a8b8 b6d7 b8a7 d8c8 a7a8 c5e6 b4d5 d4c6 d5e7 c6e7 a8a7 e7c6 a7a6 e6c7
info depth 1 seldepth 1 multipv 13 score mate 35 nodes 0 nps 0 tbhits 13 time 1 pv f1h2 f8e6 h2f3 e6f4 h1g3 e8d7 e1d2 d7c6 d2e3 f4e6 g3f5 c6c5 e3e4 e6c7 f3d2 c7d5 g1e2 d5f6 e4e5 f6g4 e5e6 g4f2 f5e3 f2d3 d2e4 c5b4 e6d5 b4a5 e2d4 d3f4 d5c4 a5b6 e4f6 b6a5 f6d7 a5a6 e3f5 a6b7 c4b5 f4d5 d7c5 b7c8 b5c6 d5b4 c6d6 c8d8 f5e7 d8e8 d6e6 b4a2 d4b5 a2b4 b5c7 e8f8 e6f6 b4d5 c7d5 f8e8 e7c6 e8f8 c5d3 f8g8 f6g6 g8h8 d3e5 h8g8 d5f6 g8h8 e5f7