EGTB Testsuite

[Jouni]

Dann: your positions are not good for EGTB testing. Rybka solves about 72/75 without tablebases And may be also 72 with them.

Jouni

[Kirill Kryukov]

Thanks for the positions! I added them into the list to analyze when I have time.

In other news, I updated the introduction post with new information.

[Kirill Kryukov]

And another KRPPKQ

[D]3k3q/2R5/1P6/8/8/8/4P3/2K5 w - - 0 1

Rc4 wins

Engines prefer Kingmoves

Sorry, I have to reject this position. Most of engines I tried choose Rc4 very soon without any tablebases, even without understanding it is a draw. (Though they often change their preference to other moves later).

[Kirill Kryukov]

And another KRPPKQ

[D]3k3q/2R5/1P6/8/8/8/4P3/2K5 w - - 0 1

Rc4 wins

Engines prefer Kingmoves

Also easy for Sage, without tablebases ...

FEN: 3k3q/2R5/1P6/8/8/8/4P3/2K5 w - - 0 1

Sage 3.38:
4 00:00 284 2.184 0.00 Kc1b1 Qh8h1+
5 00:00 366 2.815 0.00 Kc1b1 Qh8h1+
6 00:00 704 5.415 0.00 Kc1b1 Qh8h1+ Kb1a2 Qh1g2 Ka2a1
7 00:00 1.676 12.892 0.00 Kc1b1 Qh8h1+ Kb1a2 Qh1g2 Ka2a1 Qg2xe2
8 00:00 9.987 76.823 0.00 Kc1d1 Qh8d4+ Kd1c2 Qd4xb6 Rc7c3 Qb6a5 Kc2b2
9 00:00 39.128 244.550 0.00 Kc1c2 Qh8d4 Rc7c3 Qd4xb6 e2e3 Qb6g6+ Rc3d3+ Kd8e8 Kc2d2
10 00:00 198.450 640.161 0.00 Rc7c4 Qh8h1+ Kc1c2 Qh1e1 Kc2b3 Qe1xe2 Rc4d4+ Kd8c8 b6b7+ Kc8xb7 Kb3c3
11 00:00 398.409 766.171 0.00 Rc7c4 Qh8h1+ Kc1c2 Qh1e1 Kc2b3 Qe1xe2 Rc4d4+ Kd8c8 b6b7+ Kc8xb7 Rd4b4+ Kb7c8 Kb3c3
12 00:01 911.310 893.441 0.00 Rc7c4 Qh8h1+ Kc1c2 Qh1e1 Kc2d3 Qe1g1 Kd3c2 Qg1xb6 Rc4c3 Kd8e7 Rc3d3
13 00:03 3.031.045 935.507 -0.01 Rc7c4 Qh8h6+ Kc1c2 Qh6xb6 Rc4c3 Kd8e7 Rc3d3 Qb6a7 Kc2b2 Qa7b8+ Kb2c2 Qb8c7+

Regards
Dave

Thanks Dave!

If you have chance, could you analyze some of the other proposed positions? This would help a lot!

[David Dahlem]

quote]
Thanks Dave!

If you have chance, could you analyze some of the other proposed positions? This would help a lot![/quote]

Sorry but i just don't have any spare time to analyze those postions.

Regards
Dave

[Kirill Kryukov]

Try this one please:

[D]2k4q/3R4/1P6/8/8/8/4P3/2K5 w - - 0 1

only Rd3 draws (forming a fortress)

Rc7 loses in 56

Most of engines I tried find 1.Rd3 in about a second without tablebases. Yes, it is not easy to construct a good endgame tablebase test. Thanks for trying though!

[Cubeman]

And another KRPPKQ

[D]3k3q/2R5/1P6/8/8/8/4P3/2K5 w - - 0 1

Rc4 wins

Engines prefer Kingmoves

Sure you mean Rc4 Draws!

[tano-urayoan]

[d] 8/8/7p/5p1k/5Q2/3q2K1/7P/8 w - - 0 59

This game was played between Vaganian - Sunye Rio de Janeiro Interzonal 1979. Here Qf3+ was played after the queens were exchange black played Kg5 and we arrived at this position.

[d] 8/8/7p/5pk1/8/5K2/7P/8 w - - 0 0

Here Ke2 draws.

If the first position does not help maybe the second one for a basic test.

P.s. Here is the complete game: [Event "Rio de Janeiro Interzonal"]
[Site "Rio de Janeiro"]
[Date "1979"]
[White "Vaganian, Rafael A"]
[Black "Sunye Neto, Jaime"]
[Result "0-1"]
1. d4 Nf6 2. c4 e6 3. Nf3 b6 4. a3 d5 5. cxd5 exd5 6. Nc3 Be7 7. g3 O-O 8. Bg2 Bb7 9. O-O c5 10. Ne5 Nc6 11. Nxc6 Bxc6 12. dxc5 bxc5 13. Bg5 Rb8 14. Rb1 h6 15. Bxf6 Bxf6 16. Qc2 Qd6 17. Rfd1 Bxc3 18. bxc3 Rxb1 19. Qxb1 Rb8 20. Qd3 Qe5 21. Qa6 Bb5 22. Qxa7 Bxe2 23. Re1 d4 24. cxd4 cxd4 25. Bf1 d3 26. f4 Qe8 27. Bxe2 Rb2 28. Qf2 Rxe2 29. Rxe2 dxe2 30. Qe1 Qe3+ 31. Kg2 g5 32. a4 gxf4 33. gxf4 Qxf4 34. Qxe2 Qxa4 35. Qe5 Qg4+ 36. Kf2 Kh7 37. Qb8 Qf5+ 38. Kg3 Kg7 39. Kg2 Kg6 40. Qd6+ Kh5 41. Qc7 Qd5+ 42. Kf2 f6 43. Qc3 Qf5+ 44. Kg2 Qg5+ 45. Kf2
Kh4 46. Qf3 Qe5 47. Kg2 Kg5 48. Qb3 Qe2+ 49. Kg3 Qg4+ 50. Kf2 Kh4 51. Qc3 Qf4+ 52. Kg2 Qg5+ 53. Kf2 Qe5 54. Qc4+ Kh5 55. Kf3 f5 56. Qf4 Qc3+ 57. Kg2 Qc2+ 58. Kg3 Qd3+ 59. Qf3+ Qxf3+ 60. Kxf3 Kg5 61. Kg3 h5 62. Kf3 h4 63. Kg2 Kg4 64. Kf2 Kf4 65. Ke2 Ke4 66. Kf2 Kd3 67. Kf3 h3 0-1

[Kirill Kryukov]

[d] 8/8/7p/5p1k/5Q2/3q2K1/7P/8 w - - 0 59

Nice! Do you know if 1.Kf2 loses or draws too? A good EGTB test should have only one solution.

This game was played between Vaganian - Sunye Rio de Janeiro Interzonal 1979. Here Qf3+ was played after the queens were exchange black played Kg5 and we arrived at this position.

[d] 8/8/7p/5pk1/8/5K2/7P/8 w - - 0 0

Here Ke2 draws.

If the first position does not help maybe the second one for a basic test.

P.s. Here is the complete game: [Event "Rio de Janeiro Interzonal"]
[Site "Rio de Janeiro"]
[Date "1979"]
[White "Vaganian, Rafael A"]
[Black "Sunye Neto, Jaime"]
[Result "0-1"]
1. d4 Nf6 2. c4 e6 3. Nf3 b6 4. a3 d5 5. cxd5 exd5 6. Nc3 Be7 7. g3 O-O 8. Bg2 Bb7 9. O-O c5 10. Ne5 Nc6 11. Nxc6 Bxc6 12. dxc5 bxc5 13. Bg5 Rb8 14. Rb1 h6 15. Bxf6 Bxf6 16. Qc2 Qd6 17. Rfd1 Bxc3 18. bxc3 Rxb1 19. Qxb1 Rb8 20. Qd3 Qe5 21. Qa6 Bb5 22. Qxa7 Bxe2 23. Re1 d4 24. cxd4 cxd4 25. Bf1 d3 26. f4 Qe8 27. Bxe2 Rb2 28. Qf2 Rxe2 29. Rxe2 dxe2 30. Qe1 Qe3+ 31. Kg2 g5 32. a4 gxf4 33. gxf4 Qxf4 34. Qxe2 Qxa4 35. Qe5 Qg4+ 36. Kf2 Kh7 37. Qb8 Qf5+ 38. Kg3 Kg7 39. Kg2 Kg6 40. Qd6+ Kh5 41. Qc7 Qd5+ 42. Kf2 f6 43. Qc3 Qf5+ 44. Kg2 Qg5+ 45. Kf2
Kh4 46. Qf3 Qe5 47. Kg2 Kg5 48. Qb3 Qe2+ 49. Kg3 Qg4+ 50. Kf2 Kh4 51. Qc3 Qf4+ 52. Kg2 Qg5+ 53. Kf2 Qe5 54. Qc4+ Kh5 55. Kf3 f5 56. Qf4 Qc3+ 57. Kg2 Qc2+ 58. Kg3 Qd3+ 59. Qf3+ Qxf3+ 60. Kxf3 Kg5 61. Kg3 h5 62. Kf3 h4 63. Kg2 Kg4 64. Kf2 Kf4 65. Ke2 Ke4 66. Kf2 Kd3 67. Kf3 h3 0-1

Thanks, I added the second one as a basic test. Some programs find 1.Ke2 very soon, but on the other hand some programs are troubled to find it.

[tano-urayoan]

[d] 8/1k6/1p1r4/5K2/8/8/8/2R5 w - - 0 1

This is another position that is difficult. Here just Ke4 draws. Maybe another basic test.