KNN - KP ending and Rybka= surprise!

[Jouni]

I thought that ending is very difficult and needs tablebases. But not for Rybka at all. It won all my testgames against Naum and Cyclone using KNNKP bitbases. See here:

I am surprised!

[Event "NN-P"]
[Site "?"]
[Date "2009.03.20"]
[Round "1"]
[White "Rybka 3 1-cpu 32-bit"]
[Black "Cyclone 3.4"]
[Result "1-0"]
[Annotator "0.91;48.63"]
[SetUp "1"]
[FEN "8/3kp3/8/8/4NN2/3K4/8/8 w - - 0 0"]
[PlyCount "85"]
[TimeControl "60/180:0/0:0/0"]

1. Kc4 {Both last book move 0.91/12 10} Kc6 {48.63/16 6}
2. Ne6 {(Ng6) 0.91/12 3} Kd7 {(Kb6) 48.06/18 6} 3. Kd5 {0.98/13 6} Ke8 {
47.93/18 4} 4. Nd4 {(Kc6) 0.98/13 5} Kf7 {48.06/18 5} 5. Ke5 {(Nc5) 0.98/13 7}
Kg6 {48.09/18 5} 6. Nf3 {(Ne2) 0.98/13 4} Kf7 {(Kh5) 47.83/19 5} 7. Kd5 {
(Nfd2) 0.99/13 5} Kg7 {(Ke8) 47.93/19 5} 8. Ke6 {0.99/13 3} Kf8 {
(Kg6) 47.93/19 4} 9. Ne5 {(Nc5) 1.14/14 6} Ke8 {(Kg7) 47.93/19 3} 10. Nf7 {
(Nc6) 1.14/14 5} Kf8 {51.93/4 0} 11. Ng3 {(Nd2) 1.14/15 2} Kg7 {47.03/21 5} 12.
Ne2 {(Nh5+) 1.14/16 7} Kf8 {(Kg8) 47.11/22 4} 13. Ne5 {(Nh6) 1.14/16 6} Kg7 {
(Kg8) 47.29/21 4} 14. Nf4 {1.14/15 7} Kf8 {(Kg8) 47.29/21 4} 15. Ng2 {
(Kf5) 1.14/14 3} Ke8 {47.29/21 4} 16. Nf7 {(Ng4) 1.14/14 2} Kf8 {51.93/4 0} 17.
Ne3 {(Ng5) 1.13/14 3} Kg7 {47.27/22 4} 18. Nd5 {(Ne5) 1.14/16 5} Kh7 {
(Kg8) 47.29/21 4} 19. Nf4 {(Nb6) 1.02/14 4} Kg8 {(Kg7) 47.21/22 5} 20. Nh6+ {
(Nh5) 1.14/15 3} Kf8 {47.13/22 7} 21. Nh5 {(Nf5) 1.14/14 6} Ke8 {51.83/4 0} 22.
Nf7 {(Nf4) 1.14/14 1} Kf8 {51.93/4 0} 23. Ne5 {(Nf4) 1.14/16 3} Ke8 {47.27/21 2
} 24. Nc6 {1.14/15 4} Kf8 {51.93/4 0} 25. Ng3 {(Nd4) 1.14/14 1} Kg7 {47.07/21 3
} 26. Ne5 {(Nf1) 0.99/13 4} Kf8 {(Kh6) 47.03/21 3} 27. Nf5 {(Nd7+) 1.14/14 2}
Ke8 {47.27/21 2} 28. Nf7 {(Nd4) 1.15/15 3} Kf8 {51.93/4 0} 29. Nd8 {
(Nd4) 1.03/14 3} Ke8 {46.34/24 3} 30. Nb7 {(Nc6) 1.03/15 2} Kf8 {51.93/4 0} 31.
Na5 {(Ne3) 1.03/14 3} Kg8 {(Ke8) 47.26/21 3} 32. Nc4 {(Ne3) 1.02/14 4} Kf8 {
47.14/21 3} 33. Nd4 {(Nce3) 1.10/13 1} Kg7 {47.81/19 3} 34. Ne5 {
(Na3) 1.03/13 2} Kf8 {(Kh6) 47.29/21 3} 35. Kf5 {(Nd7+) 1.21/13 1} Ke8 {
47.49/21 3} 36. Ndc6 {1.21/12 1} Kf8 {48.92/21 3} 37. Kg6 {1.21/12 1} Kg8 {
(e6) 49.72/21 3} 38. Nd7 {#8/9 0} Kh8 {50.52/21 2} 39. Nd4 {(Nd8) #6/6 0} Kg8 {
(e6) 50.69/21 3} 40. Nf5 {#5/4 0} Kh8 {51.49/22 3} 41. Nh6 {#3/3 0} e5 {
52.29/63 0} 42. Nf6 {#2/3 0} e4 {52.36/4 0} 43. Nf7# {#1/3 0} 1-0

[Event "NN-P"]
[Site "?"]
[Date "2009.03.20"]
[Round "3"]
[White "Rybka 3 1-cpu 32-bit"]
[Black "Cyclone 3.4"]
[Result "1-0"]
[Annotator "0.42;47.86"]
[SetUp "1"]
[FEN "6k1/7p/8/8/8/8/1NN2K2/8 w - - 0 1"]
[PlyCount "87"]
[TimeControl "60/180:0/0:0/0"]

1. Kg3 {Both last book move 0.42/13 9} Kg7 {47.86/18 6} 2.
Nc4 {(Nd1) 0.43/13 7} Kh6 {(h5) 47.86/18 6} 3. Kh4 {0.44/13 5} Kg6 {47.06/21 5}
4. Nb4 {(N2e3) 0.43/14 14} Kf5 {(h5) 47.69/19 5} 5. Kh5 {0.44/14 4} Ke4 {
47.69/19 3} 6. Nd6+ {(Kg5) 0.45/15 6} Ke5 {(Kd4) 47.01/21 5} 7. Nf7+ {0.46/15 3
} Kf5 {(Kd4) 47.06/21 7} 8. Nh6+ {0.46/15 6} Kf4 {(Ke6) 47.06/21 5} 9. Kh4 {
(Na6) 0.47/16 7} Ke4 {47.06/21 4} 10. Kg4 {0.47/15 4} Ke5 {47.06/21 4} 11. Kg5
{0.48/15 11} Ke4 {(Kd4) 47.09/21 5} 12. Kf6 {(Nf7) 0.48/12 3} Kd4 {
(Kf4) 47.94/18 5} 13. Kf5 {0.48/11 5} Kc4 {47.96/18 11} 14. Na6 {
(Nc6) 0.48/14 5} Kd5 {(Kd4) 48.76/16 3} 15. Nc7+ {0.48/12 3} Kd6 {
(Kd4) 47.98/19 4} 16. Ne6 {0.49/13 2} Kd5 {48.86/16 4} 17. Nf4+ {
(Nf7) 0.49/12 1} Kd4 {48.90/16 3} 18. Nh5 {(Nf7) 0.49/12 5} Kd5 {48.76/16 2}
19. Nf7 {0.50/13 5} Kd4 {(h6) 48.84/15 3} 20. Nd6 {(Nf6) 0.50/12 3} Kd5 {
47.94/18 3} 21. Ne8 {(Ne4) 0.50/12 3} Kd4 {(Kc4) 48.78/15 3} 22. Nef6 {
0.50/11 1} Ke3 {47.89/18 3} 23. Ke5 {(Nf4) 0.50/11 1} Ke2 {(Kf3) 48.77/16 3}
24. Ke4 {(Nf4+) 0.50/10 2} Kd1 {(Kf2) 49.00/15 2} 25. Kd3 {(Ng4) 0.52/11 3} Kc1
{(Ke1) 48.81/15 3} 26. Nd5 {0.52/9 2} Kb2 {(Kd1) 49.04/16 2} 27. Ne3 {
(Ng3) 0.53/10 2} Kb3 {(Kc1) 48.74/15 3} 28. Nc2 {(Nf5) 0.53/8 2} Ka4 {
(Kb2) 49.72/13 2} 29. Kc4 {0.57/9 1} Ka5 {48.79/15 2} 30. Nd4 {(Kd5) 0.54/10 3}
Kb6 {(Ka4) 48.82/15 2} 31. Kd5 {0.56/8 2} Kc7 {(Ka5) 48.87/15 2} 32. Ke6 {
(Nf6) 0.56/10 2} Kd8 {(Kb6) 48.81/15 2} 33. Kd6 {(Nf5) 0.73/10 4} Ke8 {
48.69/16 2} 34. Nf5 {(Ne6) 0.73/11 1} Kf7 {47.97/18 2} 35. Ne7 {(Ke5) 0.73/11 2
} Ke8 {48.69/16 1} 36. Ke6 {(Nd5) 0.58/11 2} Kd8 {47.99/18 2} 37. Nd5 {
(Nf5) 0.60/11 1} Ke8 {(Kc8) 49.07/17 1} 38. Nc7+ {(Ng7+) 0.59/10 1} Kf8 {
(Kd8) 48.02/18 2} 39. Kf6 {(Nf4) #8/9 0} Kg8 {(h6) 50.62/18 1} 40. Ne6 {#6/6 0}
Kh8 {(h6) 51.42/19 2} 41. Kf7 {#4/4 0} h6 {52.22/4 0} 42. Nef4 {#3/3 0} Kh7 {
51.91/4 0} 43. Nf6+ {(Kf6) #2/3 0} Kh8 {#1/4 0} 44. Ng6# {#1/3 0} 1-0

[Event "NN-P"]
[Site "?"]
[Date "2009.03.20"]
[Round "1"]
[White "Rybka 3 1-cpu 32-bit"]
[Black "Naum 4"]
[Result "1-0"]
[Annotator "0.91;0.33"]
[SetUp "1"]
[FEN "8/3kp3/8/8/4NN2/3K4/8/8 w - - 0 0"]
[PlyCount "79"]
[TimeControl "60/180:0/0:0/0"]

1. Kc4 {Both last book move 0.91/12 10}
Kc6 {0.33/15 6} 2. Ne6 {(Nd3) 0.91/12 3} Kd7 {(Kb6) 0.33/16 2} 3. Kd5 {
0.98/13 6} Ke8 {0.33/15 1} 4. Nd4 {(N4g5) 0.98/13 5} e6+ {(Kf7) 0.33/15 3} 5.
Kd6 {(Ke5) 0.99/13 5} Kf7 {0.33/15 1} 6. Ke5 {(Nc6) 0.99/13 5} Kg7 {
(Ke7) 0.33/15 2} 7. Nb5 {(Nc6) 0.99/13 5} Kf7 {0.33/16 2} 8. Nf6 {
(Nc5) 0.99/14 7} Kf8 {0.33/17 2} 9. Nd6 {(Nd7+) 0.99/15 7} Ke7 {0.33/18 3} 10.
Nc4 {(Nde4) 0.99/15 4} Kf7 {(Kf8) 0.33/18 3} 11. Na5 {(Nb6) 0.99/15 5} Ke7 {
(Kg6) 0.34/18 3} 12. Nb3 {(Nc6+) 0.99/15 4} Kf8 {0.34/18 6} 13. Nd7+ {
(Nd4) 0.99/15 5} Ke8 {(Kf7) 0.33/17 2} 14. Nbc5 {0.99/15 3} Kf7 {0.33/17 2} 15.
Nf6 {(Nb8) 0.99/15 4} Kf8 {(Kg6) 0.33/18 5} 16. Ng4 {(Ncd7+) 0.99/15 4} Ke7 {
(Kf7) 0.34/18 10} 17. Nf2 {(Kd4) 0.99/14 3} Kf7 {0.33/17 2} 18. Nce4 {
(Nfe4) 0.99/14 3} Ke7 {(Ke8) 0.33/17 1} 19. Nf6 {(Nh3) 0.99/14 3} Kf7 {
(Kd8) 0.33/19 3} 20. Nd3 {(N2e4) 0.99/16 7} Ke7 {(Kg6) 0.33/18 2} 21. Ne1 {
(Nb4) 0.99/14 8} Kf8 {(Kd8) 0.33/19 3} 22. Nc2 {(Nf3) 0.99/14 2} Ke7 {0.34/18 2
} 23. Na3 {(Nd4) 0.99/15 3} Kf7 {0.33/19 3} 24. Nb1 {(Nc4) 0.99/15 2} Ke7 {
(Kf8) 0.33/19 2} 25. Nd2 {(Nc3) 0.99/15 2} Kf8 {0.34/19 4} 26. Nb3 {0.99/15 4}
Ke7 {(Kf7) 0.34/19 3} 27. Nd4 {0.99/15 2} Kd8 {(Kf7) 0.34/18 3} 28. Kd6 {
0.92/13 8} Kc8 {(e5) 0.34/17 3} 29. Ne4 {(Nf3) 0.99/13 4} Kd8 {(Kb7) 0.34/17 7}
30. Nc6+ {(Nf3) 1.07/12 2} Kc8 {0.34/17 3} 31. Na5 {(Ne5) 1.07/13 4} e5 {
0.34/16 2} 32. Nc4 {(Kd5) 1.07/12 1} Kb7 {(Kb8) 0.34/15 1} 33. Kd7 {
(Kd5) 1.07/12 2} Ka6 {0.35/16 2} 34. Kc6 {#8/11 0} Ka7 {0.35/3 0} 35. Nc5 {
#7/8 0} Kb8 {(Ka8) #7/12 0} 36. Nd6 {(Kd7) #5/6 0} Ka7 {(e4) #5/9 0} 37. Kc7 {
#4/4 0} e4 {(Ka8) #3/3 0} 38. Nb5+ {#3/3 0} Ka8 {#2/3 0} 39. Nd7 {(Na4) #2/3 0}
e3 {#1/3 0} 40. Nb6# {#1/3 0} 1-0

[Event "NN-P"]
[Site "?"]
[Date "2009.03.20"]
[Round "3"]
[White "Rybka 3 1-cpu 32-bit"]
[Black "Naum 4"]
[Result "1-0"]
[Annotator "0.42;0.30"]
[SetUp "1"]
[FEN "6k1/7p/8/8/8/8/1NN2K2/8 w - - 0 1"]
[PlyCount "61"]
[TimeControl "60/180:0/0:0/0"]

1. Kg3 {Both last book move 0.42/12 17} Kf7
{0.30/15 11} 2. Nd3 {(Nc4) 0.43/13 10} Ke6 {(Kf6) 0.32/13 9} 3. Ne3 {
(Kg4) 0.44/12 5} Kf6 {0.32/15 3} 4. Kh4 {0.44/12 13} Kg7 {(Kg6) 0.32/15 13} 5.
Nf4 {(Kh5) 0.45/12 6} Kf6 {0.32/16 2} 6. Nh5+ {(Kh5) 0.47/13 12} Ke5 {0.32/16 3
} 7. Kg5 {0.48/13 2} Kd4 {(h6+) 0.32/16 4} 8. Kf4 {(Nf5+) 0.50/13 3} h6 {
(Kd3) 0.32/16 3} 9. Ng4 {(Nf6) 0.51/13 3} Kc3 {(Kd5) 0.32/16 3} 10. Ke4 {
(Nhf6) 0.52/13 6} Kb4 {(Kd2) 0.32/15 3} 11. Kd4 {(Kf5) 0.52/12 4} Kb5 {
(Kb3) 0.32/15 6} 12. Ne5 {(Ke5) 0.53/12 3} Ka4 {(Kb4) 0.32/15 1} 13. Kc4 {
(Ke4) 0.54/12 7} Ka3 {0.32/15 1} 14. Nd3 {(Kd5) 0.54/11 2} Ka4 {0.32/15 5} 15.
Nb2+ {(Kd5) 0.66/10 6} Ka5 {(Ka3) 0.32/14 2} 16. Kc5 {(Kd5) 0.66/11 8} Ka6 {
0.30/3 0} 17. Nc4 {0.76/11 2} Ka7 {(Kb7) 0.32/14 1} 18. Kd5 {(Ne5) 0.76/11 3}
Kb7 {0.32/12 1} 19. Kd6 {(Nd6+) 0.76/11 3} Ka6 {(Kb8) 0.32/15 2} 20. Kc6 {
(Ne5) 0.95/12 2} Ka7 {0.26/3 0} 21. Nd6 {(Nf6) 0.87/12 3} Ka6 {0.32/14 2} 22.
Nb7 {(Kd5) 0.87/12 2} Ka7 {0.32/3 0} 23. Nc5 {0.87/12 1} Kb8 {#10/14 0} 24. Kd7
{#8/11 0} Ka8 {(Ka7) #9/12 0} 25. Kc7 {#7/9 0} Ka7 {0.17/3 0} 26. Nf4 {#6/7 0}
h5 {(Ka8) #5/8 0} 27. Nfe6 {(Nd5) #5/4 0} h4 {#4/5 6} 28. Nd4 {#4/3 0} h3 {
(Ka8) #3/3 0} 29. Nc6+ {(Nb5+) #3/3 0} Ka8 {#2/3 0} 30. Nd7 {(Na4) #2/3 0} h2 {
#1/3 0} 31. Nb6# {#1/3 0} 1-0

Jouni

[Jouni]

Addition with Cyclone as white (my only bitbase engine):

[Event "NN-P"]
[Site "?"]
[Date "2009.03.20"]
[Round "2"]
[White "Cyclone 3.4"]
[Black "Rybka 3 1-cpu 32-bit"]
[Result "1/2-1/2"]
[Annotator "47.58;0.93"]
[SetUp "1"]
[FEN "8/3kp3/8/8/4NN2/3K4/8/8 w - - 0 0"]
[PlyCount "108"]
[TimeControl "60/180:0/0:0/0"]

1. Kc4 {Both last book move 0.91/12 10} Kc7 {0.93/12 8} 2.
Kd5 {(Nd3) 47.58/19 4} Kb6 {(Kd7) 0.89/13 4} 3. Nc5 {(Nd3) 48.56/17 4} e5 {
(Ka5) 0.58/12 5} 4. Ng2 {47.71/20 5} e4 {(Ka5) 0.62/13 5} 5. Ne3 {48.42/17 4}
Kc7 {0.62/13 2} 6. Na4 {48.42/17 6} Kd7 {0.62/14 6} 7. Nb6+ {(Nc3) 48.37/17 4}
Ke7 {0.62/13 3} 8. Ke5 {48.51/17 4} Kf7 {(Ke8) 0.62/13 2} 9. Nc8 {
(Nbd5) 47.78/19 4} Ke8 {(Kg6) 0.62/14 5} 10. Ke6 {47.76/20 10} Kd8 {0.62/14 2}
11. Nb6 {(Nd6) 47.62/20 5} Kc7 {0.62/15 6} 12. Nbd5+ {47.66/20 7} Kc6 {
0.62/14 3} 13. Nb4+ {(Ne7+) 47.76/20 4} Kc5 {(Kb5) 0.62/15 5} 14. Nbc2 {
46.94/23 4} Kc6 {0.62/15 4} 15. Ke7 {47.66/20 3} Kc5 {0.63/15 6} 16. Kd7 {
47.78/20 3} Kb5 {0.63/14 2} 17. Kd6 {47.84/20 3} Ka4 {0.63/14 2} 18. Kc5 {
(Nd4) 47.84/20 4} Kb3 {0.66/14 4} 19. Kd4 {47.86/20 3} Ka4 {(Kb2) 0.66/14 2}
20. Kc4 {47.66/20 4} Ka5 {0.66/13 0} 21. Nd4 {(Kc5) 47.76/20 6} Kb6 {0.63/13 4}
22. Kd5 {47.42/20 8} Kc7 {(Kb7) 0.63/13 2} 23. Ke6 {47.66/20 4} Kb6 {
(Kd8) 0.63/14 3} 24. Kd6 {47.66/20 4} Kb7 {(Ka5) 0.63/14 4} 25. Ne6 {
(Nc6) 47.66/20 4} Kb6 {0.63/13 1} 26. Nc7 {(Nf4) 47.62/20 5} Kb7 {0.65/14 3}
27. Ncd5 {46.81/22 2} Ka6 {0.66/14 8} 28. Kc6 {47.42/20 1} Ka5 {0.66/13 2} 29.
Kc5 {47.82/20 4} Ka6 {0.65/13 4} 30. Nb6 {(Nf4) 47.66/20 4} Kb7 {0.64/13 2} 31.
Nbc4 {(Nd7) 47.42/20 3} Kc7 {0.62/12 2} 32. Kd5 {(Ne5) 47.28/20 4} Kd7 {
0.62/13 2} 33. Ne5+ {(Nd6) 46.84/20 2} Ke7 {(Kc7) 0.62/13 2} 34. N5g4 {
(Ng6+) 47.09/19 1} Kf7 {(Kd8) 0.62/14 4} 35. Kc4 {(Ke5) 47.15/19 1} Ke7 {
0.62/13 2} 36. Nf2 {(Kc5) 47.18/19 1} Ke6 {0.62/13 3} 37. Kc3 {(Kc5) 47.18/19 1
} Ke7 {(Ke5) 0.59/12 3} 38. Nh1 {(Nh3) 47.13/20 1} Kf6 {(Ke6) 0.59/13 3} 39.
Kd2 {(Kd4) 47.15/19 1} Ke5 {(Ke7) 0.44/12 2} 40. Ng3 {47.15/20 1} Kf4 {
(Kf6) 0.50/13 2} 41. Ne2+ {(Ngf5) 46.99/20 2} Kf3 {(Ke5) 0.50/13 2} 42. Nd4+ {
(Nc3) 47.30/20 1} Kf4 {0.50/13 2} 43. Nc6 {(Ndf5) 47.11/20 3} Kf3 {0.50/12 3}
44. Ne5+ {(Nb4) 47.21/20 2} Kf4 {0.50/14 2} 45. Nd7 {(N5c4) 47.01/20 1} Kg5 {
(Kf3) 0.50/12 1} 46. Ke1 {(Nb6) 47.18/19 1} Kg6 {(Kf4) 0.50/13 3} 47. Nb6 {
(Ke2) 47.15/20 1} Kf6 {0.59/13 4} 48. Nbd5+ {47.18/20 1} Kf7 {(Ke6) 0.59/14 2}
49. Kf2 {(Ke2) 0.00/19 3} Ke6 {0.59/14 2} 50. Ke2 {0.00/21 1} Kd6 {0.25/13 2}
51. Kd2 {(Nc3) 0.00/25 1} Kc5 {(Ke5) 0.00/18 1} 52. Kc3 {(Nc3) 0.00/27 1} Kb5 {
0.00/22 2} 53. Kd4 {0.00/34 1} Ka5 {(Kc6) 0.00/59 0} 54. Nc3 {(Ne7) 0.00/63 0}
Kb4 {Draw accepted 0.00/59 0} 1/2-1/2

[Event "NN-P"]
[Site "?"]
[Date "2009.03.20"]
[Round "4"]
[White "Cyclone 3.4"]
[Black "Rybka 3 1-cpu 32-bit"]
[Result "1/2-1/2"]
[Annotator "47.54;0.43"]
[SetUp "1"]
[FEN "6k1/7p/8/8/8/8/1NN2K2/8 w - - 0 1"]
[PlyCount "108"]
[TimeControl "60/180:0/0:0/0"]

1. Kg3 {Both last book move 0.42/13 9} Kf7 {0.43/12 7} 2.
Nd1 {(Nd3) 47.54/19 6} Ke6 {(Kf6) 0.41/12 5} 3. Kf4 {(Kg4) 47.54/19 3} h5 {
(Kd5) 0.34/12 4} 4. Nf2 {48.35/17 5} h4 {(Kd5) 0.34/12 5} 5. Nh3 {48.22/17 4}
Kd5 {(Kd6) 0.35/13 4} 6. Kf5 {(Kf3) 48.34/17 3} Kc4 {0.35/14 7} 7. Ke4 {
(Ne1) 47.57/20 5} Kc5 {0.36/14 8} 8. Ke5 {(Ne3) 47.64/20 8} Kc4 {0.36/15 5} 9.
Ne1 {47.62/20 6} Kc3 {0.36/15 4} 10. Kf5 {(Ke4) 47.36/20 6} Kd4 {0.35/15 8} 11.
Nf3+ {47.36/20 3} Ke3 {(Kc4) 0.35/15 3} 12. Ne5 {46.47/23 4} Kd4 {0.35/15 6}
13. Ke6 {(Ng4) 47.12/20 4} Ke4 {(Ke3) 0.35/15 9} 14. Ng4 {(Nf7) 47.16/20 5} Kf3
{(Kd4) 0.35/15 2} 15. Ngf2 {(Kf5) 46.63/23 4} Ke2 {(Kg2) 0.36/16 6} 16. Ke5 {
(Ne4) 46.56/23 10} Kf3 {(Ke3) 0.36/16 4} 17. Kd4 {46.78/23 3} Ke2 {0.36/15 4}
18. Ne4 {46.84/22 5} Kf3 {0.36/14 3} 19. Neg5+ {46.77/23 3} Ke2 {0.36/14 1} 20.
Ng1+ {(Ke4) 46.76/23 11} Kf2 {(Kf1) 0.36/16 4} 21. N5h3+ {46.56/23 7} Kg3 {
(Kg2) 0.36/16 2} 22. Ke3 {(Ke4) 46.77/23 2} Kg4 {(Kg2) 0.36/15 2} 23. Ke4 {
46.49/23 9} Kg3 {0.36/17 3} 24. Kf5 {45.97/25 1} Kg2 {0.36/17 2} 25. Kf4 {
45.97/25 1} Kf1 {0.36/16 1} 26. Kf3 {(Nf3) 45.95/26 2} Ke1 {0.36/13 0} 27. Kg4
{(Ke3) 45.87/23 2} Kd2 {0.35/15 3} 28. Nf3+ {46.88/20 2} Ke3 {(Kd3) 0.35/15 2}
29. Ne5 {(Nfg5) 46.26/22 2} Kd4 {0.35/15 2} 30. Nc6+ {(Kf5) 47.65/17 1} Kd5 {
0.35/14 2} 31. Ne7+ {47.18/20 1} Ke4 {(Kc4) 0.35/14 4} 32. Nf5 {
(Ng6) 46.93/20 1} Ke5 {(Kd5) 0.35/15 3} 33. Kg5 {(Ng7) 46.86/21 1} Ke4 {
(Kd5) 0.35/14 1} 34. Kg6 {(Ng7) 46.67/21 1} Kf3 {(Kd3) 0.35/14 2} 35. Kh5 {
46.03/23 1} Ke4 {0.35/15 1} 36. Nd6+ {(Nh6) 46.74/20 1} Kd5 {(Ke5) 0.35/15 1}
37. Nb5 {(Ne8) 46.83/20 1} Kc5 {(Ke4) 0.35/16 2} 38. Nc3 {46.78/20 2} Kd4 {
(Kc4) 0.35/16 3} 39. Na4 {(Ne2+) 46.88/21 1} Ke3 {(Kd3) 0.35/15 2} 40. Kg4 {
46.83/20 1} Kd4 {(Ke4) 0.35/15 2} 41. Nb6 {46.63/20 2} Ke3 {(Kc5) 0.35/15 2}
42. Nc4+ {(Nd7) 46.74/20 2} Ke4 {0.35/16 3} 43. Nd6+ {46.83/20 1} Ke5 {
0.35/16 2} 44. Nf5 {45.87/22 2} Ke4 {0.35/16 3} 45. Ng7 {(Nh6) 46.49/21 1} Ke5
{0.35/16 3} 46. Nh5 {45.87/22 2} Kd4 {(Kd5) 0.35/15 1} 47. Nf6 {46.19/23 1} Ke5
{0.35/16 1} 48. Nd7+ {(Nh7) 46.98/20 1} Ke6 {(Kd6) 0.35/16 1} 49. Nc5+ {
(Nf8+) 0.00/20 2} Kd5 {0.35/17 2} 50. Nd3 {0.00/23 1} Kd4 {(Ke4) 0.35/17 8} 51.
Ndf4 {0.00/27 1} Kc3 {(Kc5) 0.00/14 1} 52. Ne2+ {(Ng5) 0.00/29 2} Kb2 {
(Kc4) 0.00/21 1} 53. Kg5 {(Nf2) 0.00/34 1} Kc2 {(Ka3) 0.00/30 1} 54. Nef4 {
(Kg4) 0.00/63 0} Kc3 {Draw accepted 0.00/59 0} 1/2-1/2



Jouni

[bob]

I thought that ending is very difficult and needs tablebases. But not for Rybka at all. It won all my testgames against Naum and Cyclone using KNNKP bitbases. See here:

I am surprised!

[Event "NN-P"]
[Site "?"]
[Date "2009.03.20"]
[Round "1"]
[White "Rybka 3 1-cpu 32-bit"]
[Black "Cyclone 3.4"]
[Result "1-0"]
[Annotator "0.91;48.63"]
[SetUp "1"]
[FEN "8/3kp3/8/8/4NN2/3K4/8/8 w - - 0 0"]
[PlyCount "85"]
[TimeControl "60/180:0/0:0/0"]

1. Kc4 {Both last book move 0.91/12 10} Kc6 {48.63/16 6}
2. Ne6 {(Ng6) 0.91/12 3} Kd7 {(Kb6) 48.06/18 6} 3. Kd5 {0.98/13 6} Ke8 {
47.93/18 4} 4. Nd4 {(Kc6) 0.98/13 5} Kf7 {48.06/18 5} 5. Ke5 {(Nc5) 0.98/13 7}
Kg6 {48.09/18 5} 6. Nf3 {(Ne2) 0.98/13 4} Kf7 {(Kh5) 47.83/19 5} 7. Kd5 {
(Nfd2) 0.99/13 5} Kg7 {(Ke8) 47.93/19 5} 8. Ke6 {0.99/13 3} Kf8 {
(Kg6) 47.93/19 4} 9. Ne5 {(Nc5) 1.14/14 6} Ke8 {(Kg7) 47.93/19 3} 10. Nf7 {
(Nc6) 1.14/14 5} Kf8 {51.93/4 0} 11. Ng3 {(Nd2) 1.14/15 2} Kg7 {47.03/21 5} 12.
Ne2 {(Nh5+) 1.14/16 7} Kf8 {(Kg8) 47.11/22 4} 13. Ne5 {(Nh6) 1.14/16 6} Kg7 {
(Kg8) 47.29/21 4} 14. Nf4 {1.14/15 7} Kf8 {(Kg8) 47.29/21 4} 15. Ng2 {
(Kf5) 1.14/14 3} Ke8 {47.29/21 4} 16. Nf7 {(Ng4) 1.14/14 2} Kf8 {51.93/4 0} 17.
Ne3 {(Ng5) 1.13/14 3} Kg7 {47.27/22 4} 18. Nd5 {(Ne5) 1.14/16 5} Kh7 {
(Kg8) 47.29/21 4} 19. Nf4 {(Nb6) 1.02/14 4} Kg8 {(Kg7) 47.21/22 5} 20. Nh6+ {
(Nh5) 1.14/15 3} Kf8 {47.13/22 7} 21. Nh5 {(Nf5) 1.14/14 6} Ke8 {51.83/4 0} 22.
Nf7 {(Nf4) 1.14/14 1} Kf8 {51.93/4 0} 23. Ne5 {(Nf4) 1.14/16 3} Ke8 {47.27/21 2
} 24. Nc6 {1.14/15 4} Kf8 {51.93/4 0} 25. Ng3 {(Nd4) 1.14/14 1} Kg7 {47.07/21 3
} 26. Ne5 {(Nf1) 0.99/13 4} Kf8 {(Kh6) 47.03/21 3} 27. Nf5 {(Nd7+) 1.14/14 2}
Ke8 {47.27/21 2} 28. Nf7 {(Nd4) 1.15/15 3} Kf8 {51.93/4 0} 29. Nd8 {
(Nd4) 1.03/14 3} Ke8 {46.34/24 3} 30. Nb7 {(Nc6) 1.03/15 2} Kf8 {51.93/4 0} 31.
Na5 {(Ne3) 1.03/14 3} Kg8 {(Ke8) 47.26/21 3} 32. Nc4 {(Ne3) 1.02/14 4} Kf8 {
47.14/21 3} 33. Nd4 {(Nce3) 1.10/13 1} Kg7 {47.81/19 3} 34. Ne5 {
(Na3) 1.03/13 2} Kf8 {(Kh6) 47.29/21 3} 35. Kf5 {(Nd7+) 1.21/13 1} Ke8 {
47.49/21 3} 36. Ndc6 {1.21/12 1} Kf8 {48.92/21 3} 37. Kg6 {1.21/12 1} Kg8 {
(e6) 49.72/21 3} 38. Nd7 {#8/9 0} Kh8 {50.52/21 2} 39. Nd4 {(Nd8) #6/6 0} Kg8 {
(e6) 50.69/21 3} 40. Nf5 {#5/4 0} Kh8 {51.49/22 3} 41. Nh6 {#3/3 0} e5 {
52.29/63 0} 42. Nf6 {#2/3 0} e4 {52.36/4 0} 43. Nf7# {#1/3 0} 1-0

[Event "NN-P"]
[Site "?"]
[Date "2009.03.20"]
[Round "3"]
[White "Rybka 3 1-cpu 32-bit"]
[Black "Cyclone 3.4"]
[Result "1-0"]
[Annotator "0.42;47.86"]
[SetUp "1"]
[FEN "6k1/7p/8/8/8/8/1NN2K2/8 w - - 0 1"]
[PlyCount "87"]
[TimeControl "60/180:0/0:0/0"]

1. Kg3 {Both last book move 0.42/13 9} Kg7 {47.86/18 6} 2.
Nc4 {(Nd1) 0.43/13 7} Kh6 {(h5) 47.86/18 6} 3. Kh4 {0.44/13 5} Kg6 {47.06/21 5}
4. Nb4 {(N2e3) 0.43/14 14} Kf5 {(h5) 47.69/19 5} 5. Kh5 {0.44/14 4} Ke4 {
47.69/19 3} 6. Nd6+ {(Kg5) 0.45/15 6} Ke5 {(Kd4) 47.01/21 5} 7. Nf7+ {0.46/15 3
} Kf5 {(Kd4) 47.06/21 7} 8. Nh6+ {0.46/15 6} Kf4 {(Ke6) 47.06/21 5} 9. Kh4 {
(Na6) 0.47/16 7} Ke4 {47.06/21 4} 10. Kg4 {0.47/15 4} Ke5 {47.06/21 4} 11. Kg5
{0.48/15 11} Ke4 {(Kd4) 47.09/21 5} 12. Kf6 {(Nf7) 0.48/12 3} Kd4 {
(Kf4) 47.94/18 5} 13. Kf5 {0.48/11 5} Kc4 {47.96/18 11} 14. Na6 {
(Nc6) 0.48/14 5} Kd5 {(Kd4) 48.76/16 3} 15. Nc7+ {0.48/12 3} Kd6 {
(Kd4) 47.98/19 4} 16. Ne6 {0.49/13 2} Kd5 {48.86/16 4} 17. Nf4+ {
(Nf7) 0.49/12 1} Kd4 {48.90/16 3} 18. Nh5 {(Nf7) 0.49/12 5} Kd5 {48.76/16 2}
19. Nf7 {0.50/13 5} Kd4 {(h6) 48.84/15 3} 20. Nd6 {(Nf6) 0.50/12 3} Kd5 {
47.94/18 3} 21. Ne8 {(Ne4) 0.50/12 3} Kd4 {(Kc4) 48.78/15 3} 22. Nef6 {
0.50/11 1} Ke3 {47.89/18 3} 23. Ke5 {(Nf4) 0.50/11 1} Ke2 {(Kf3) 48.77/16 3}
24. Ke4 {(Nf4+) 0.50/10 2} Kd1 {(Kf2) 49.00/15 2} 25. Kd3 {(Ng4) 0.52/11 3} Kc1
{(Ke1) 48.81/15 3} 26. Nd5 {0.52/9 2} Kb2 {(Kd1) 49.04/16 2} 27. Ne3 {
(Ng3) 0.53/10 2} Kb3 {(Kc1) 48.74/15 3} 28. Nc2 {(Nf5) 0.53/8 2} Ka4 {
(Kb2) 49.72/13 2} 29. Kc4 {0.57/9 1} Ka5 {48.79/15 2} 30. Nd4 {(Kd5) 0.54/10 3}
Kb6 {(Ka4) 48.82/15 2} 31. Kd5 {0.56/8 2} Kc7 {(Ka5) 48.87/15 2} 32. Ke6 {
(Nf6) 0.56/10 2} Kd8 {(Kb6) 48.81/15 2} 33. Kd6 {(Nf5) 0.73/10 4} Ke8 {
48.69/16 2} 34. Nf5 {(Ne6) 0.73/11 1} Kf7 {47.97/18 2} 35. Ne7 {(Ke5) 0.73/11 2
} Ke8 {48.69/16 1} 36. Ke6 {(Nd5) 0.58/11 2} Kd8 {47.99/18 2} 37. Nd5 {
(Nf5) 0.60/11 1} Ke8 {(Kc8) 49.07/17 1} 38. Nc7+ {(Ng7+) 0.59/10 1} Kf8 {
(Kd8) 48.02/18 2} 39. Kf6 {(Nf4) #8/9 0} Kg8 {(h6) 50.62/18 1} 40. Ne6 {#6/6 0}
Kh8 {(h6) 51.42/19 2} 41. Kf7 {#4/4 0} h6 {52.22/4 0} 42. Nef4 {#3/3 0} Kh7 {
51.91/4 0} 43. Nf6+ {(Kf6) #2/3 0} Kh8 {#1/4 0} 44. Ng6# {#1/3 0} 1-0

[Event "NN-P"]
[Site "?"]
[Date "2009.03.20"]
[Round "1"]
[White "Rybka 3 1-cpu 32-bit"]
[Black "Naum 4"]
[Result "1-0"]
[Annotator "0.91;0.33"]
[SetUp "1"]
[FEN "8/3kp3/8/8/4NN2/3K4/8/8 w - - 0 0"]
[PlyCount "79"]
[TimeControl "60/180:0/0:0/0"]

1. Kc4 {Both last book move 0.91/12 10}
Kc6 {0.33/15 6} 2. Ne6 {(Nd3) 0.91/12 3} Kd7 {(Kb6) 0.33/16 2} 3. Kd5 {
0.98/13 6} Ke8 {0.33/15 1} 4. Nd4 {(N4g5) 0.98/13 5} e6+ {(Kf7) 0.33/15 3} 5.
Kd6 {(Ke5) 0.99/13 5} Kf7 {0.33/15 1} 6. Ke5 {(Nc6) 0.99/13 5} Kg7 {
(Ke7) 0.33/15 2} 7. Nb5 {(Nc6) 0.99/13 5} Kf7 {0.33/16 2} 8. Nf6 {
(Nc5) 0.99/14 7} Kf8 {0.33/17 2} 9. Nd6 {(Nd7+) 0.99/15 7} Ke7 {0.33/18 3} 10.
Nc4 {(Nde4) 0.99/15 4} Kf7 {(Kf8) 0.33/18 3} 11. Na5 {(Nb6) 0.99/15 5} Ke7 {
(Kg6) 0.34/18 3} 12. Nb3 {(Nc6+) 0.99/15 4} Kf8 {0.34/18 6} 13. Nd7+ {
(Nd4) 0.99/15 5} Ke8 {(Kf7) 0.33/17 2} 14. Nbc5 {0.99/15 3} Kf7 {0.33/17 2} 15.
Nf6 {(Nb8) 0.99/15 4} Kf8 {(Kg6) 0.33/18 5} 16. Ng4 {(Ncd7+) 0.99/15 4} Ke7 {
(Kf7) 0.34/18 10} 17. Nf2 {(Kd4) 0.99/14 3} Kf7 {0.33/17 2} 18. Nce4 {
(Nfe4) 0.99/14 3} Ke7 {(Ke8) 0.33/17 1} 19. Nf6 {(Nh3) 0.99/14 3} Kf7 {
(Kd8) 0.33/19 3} 20. Nd3 {(N2e4) 0.99/16 7} Ke7 {(Kg6) 0.33/18 2} 21. Ne1 {
(Nb4) 0.99/14 8} Kf8 {(Kd8) 0.33/19 3} 22. Nc2 {(Nf3) 0.99/14 2} Ke7 {0.34/18 2
} 23. Na3 {(Nd4) 0.99/15 3} Kf7 {0.33/19 3} 24. Nb1 {(Nc4) 0.99/15 2} Ke7 {
(Kf8) 0.33/19 2} 25. Nd2 {(Nc3) 0.99/15 2} Kf8 {0.34/19 4} 26. Nb3 {0.99/15 4}
Ke7 {(Kf7) 0.34/19 3} 27. Nd4 {0.99/15 2} Kd8 {(Kf7) 0.34/18 3} 28. Kd6 {
0.92/13 8} Kc8 {(e5) 0.34/17 3} 29. Ne4 {(Nf3) 0.99/13 4} Kd8 {(Kb7) 0.34/17 7}
30. Nc6+ {(Nf3) 1.07/12 2} Kc8 {0.34/17 3} 31. Na5 {(Ne5) 1.07/13 4} e5 {
0.34/16 2} 32. Nc4 {(Kd5) 1.07/12 1} Kb7 {(Kb8) 0.34/15 1} 33. Kd7 {
(Kd5) 1.07/12 2} Ka6 {0.35/16 2} 34. Kc6 {#8/11 0} Ka7 {0.35/3 0} 35. Nc5 {
#7/8 0} Kb8 {(Ka8) #7/12 0} 36. Nd6 {(Kd7) #5/6 0} Ka7 {(e4) #5/9 0} 37. Kc7 {
#4/4 0} e4 {(Ka8) #3/3 0} 38. Nb5+ {#3/3 0} Ka8 {#2/3 0} 39. Nd7 {(Na4) #2/3 0}
e3 {#1/3 0} 40. Nb6# {#1/3 0} 1-0

[Event "NN-P"]
[Site "?"]
[Date "2009.03.20"]
[Round "3"]
[White "Rybka 3 1-cpu 32-bit"]
[Black "Naum 4"]
[Result "1-0"]
[Annotator "0.42;0.30"]
[SetUp "1"]
[FEN "6k1/7p/8/8/8/8/1NN2K2/8 w - - 0 1"]
[PlyCount "61"]
[TimeControl "60/180:0/0:0/0"]

1. Kg3 {Both last book move 0.42/12 17} Kf7
{0.30/15 11} 2. Nd3 {(Nc4) 0.43/13 10} Ke6 {(Kf6) 0.32/13 9} 3. Ne3 {
(Kg4) 0.44/12 5} Kf6 {0.32/15 3} 4. Kh4 {0.44/12 13} Kg7 {(Kg6) 0.32/15 13} 5.
Nf4 {(Kh5) 0.45/12 6} Kf6 {0.32/16 2} 6. Nh5+ {(Kh5) 0.47/13 12} Ke5 {0.32/16 3
} 7. Kg5 {0.48/13 2} Kd4 {(h6+) 0.32/16 4} 8. Kf4 {(Nf5+) 0.50/13 3} h6 {
(Kd3) 0.32/16 3} 9. Ng4 {(Nf6) 0.51/13 3} Kc3 {(Kd5) 0.32/16 3} 10. Ke4 {
(Nhf6) 0.52/13 6} Kb4 {(Kd2) 0.32/15 3} 11. Kd4 {(Kf5) 0.52/12 4} Kb5 {
(Kb3) 0.32/15 6} 12. Ne5 {(Ke5) 0.53/12 3} Ka4 {(Kb4) 0.32/15 1} 13. Kc4 {
(Ke4) 0.54/12 7} Ka3 {0.32/15 1} 14. Nd3 {(Kd5) 0.54/11 2} Ka4 {0.32/15 5} 15.
Nb2+ {(Kd5) 0.66/10 6} Ka5 {(Ka3) 0.32/14 2} 16. Kc5 {(Kd5) 0.66/11 8} Ka6 {
0.30/3 0} 17. Nc4 {0.76/11 2} Ka7 {(Kb7) 0.32/14 1} 18. Kd5 {(Ne5) 0.76/11 3}
Kb7 {0.32/12 1} 19. Kd6 {(Nd6+) 0.76/11 3} Ka6 {(Kb8) 0.32/15 2} 20. Kc6 {
(Ne5) 0.95/12 2} Ka7 {0.26/3 0} 21. Nd6 {(Nf6) 0.87/12 3} Ka6 {0.32/14 2} 22.
Nb7 {(Kd5) 0.87/12 2} Ka7 {0.32/3 0} 23. Nc5 {0.87/12 1} Kb8 {#10/14 0} 24. Kd7
{#8/11 0} Ka8 {(Ka7) #9/12 0} 25. Kc7 {#7/9 0} Ka7 {0.17/3 0} 26. Nf4 {#6/7 0}
h5 {(Ka8) #5/8 0} 27. Nfe6 {(Nd5) #5/4 0} h4 {#4/5 6} 28. Nd4 {#4/3 0} h3 {
(Ka8) #3/3 0} 29. Nc6+ {(Nb5+) #3/3 0} Ka8 {#2/3 0} 30. Nd7 {(Na4) #2/3 0} h2 {
#1/3 0} 31. Nb6# {#1/3 0} 1-0

Jouni

This is not surprising at all, to me. I've found the same for other endings that we as humans consider to be difficult. KQKR is an example that most computers can win moving instantly. There are others that are hard for most as well, such as KBNK, yet it is easy for a computer with a small piece of knowledge about how to win.

[Philippe]

There is no surprise. Any engine with the 5 men egtb can solve it.
By the way, stop the hype with rybka.

[Graham Banks]

By the way, stop the hype with rybka.

That's a strange thing to say.