Some nice bm and am test positions from a Rybka game

[Guenther Simon]

A few nice test positions from a Rybka game below.
Still difficult for other programs despite found by
Rybka in a 40/5 game!

Played in a 40/5 game on a P4 2.67 Ghz machine,
both used around 128MB hash, ponder off.
Winboard 4.27x(latest AS release).
From a match Rybka_10b-32 vs. Ktulu_75 49.5:18.5!
(34 starting positions with 12 plies, reversed colour
for each position)
More description -> http://rwbc.volker-pittlik.name/GS12matches.htm

bm 29. c4!! already played with slightly positive score +0.22/12
(Rybka sacks a second pawn to come back into the game, by opening
the diagonal for the W Q and create some nasty threats!)
[diag]2r1r1k1/6p1/p2Rbn1p/1pp2p2/q3pB1P/P1P1P1P1/1Q1R1P2/5BK1 w - - 0 29[/diag]
2r1r1k1/6p1/p2Rbn1p/1pp2p2/q3pB1P/P1P1P1P1/1Q1R1P2/5BK1 w - - 0 29

am 29...Bxc4?? Ktulu smelled nothing and gave still +1.47/11 for itself,
when it fell into the trap (better ...b4 or ...bxc4, not yet fully analysed, but
I believe at least that Rybka already has sufficient compensation,
even with Blacks best play)
[diag]2r1r1k1/6p1/p2Rbn1p/1pp2p2/q1P1pB1P/P3P1P1/1Q1R1P2/5BK1 b - - 0 29[/diag]
2r1r1k1/6p1/p2Rbn1p/1pp2p2/q1P1pB1P/P3P1P1/1Q1R1P2/5BK1 b - - 0 29


bm 30.Rxf6! Rybka already with crushing score +3.89/11
[diag]2r1r1k1/6p1/p2R1n1p/1pp2p2/q1b1pB1P/P3P1P1/1Q1R1P2/5BK1 w - - 0 30[/diag]
2r1r1k1/6p1/p2R1n1p/1pp2p2/q1b1pB1P/P3P1P1/1Q1R1P2/5BK1 w - - 0 30


[Event "GS12 Test 3"]
[Site "ESPRESSO"]
[Date "2005.12.06"]
[Round "2"]
[White "Rybka_10b-32"]
[Black "Ktulu 7.5"]
[Result "1-0"]
[TimeControl "40/300"]

1. c4 e5 2. Nc3 Nf6 3. Nf3 Nc6 4. g3 Bb4 5. Bg2 O-O 6. O-O Re8 7.
a3 {+0.12/11} Bxc3 {+0.42/13} 8. dxc3 {+0.12/11} d6 {+0.44/13} 9.
Qb3 {+0.09/11} e4 10. Nd4 {+0.16/11} Na5 {+0.23/12} 11. Qa2 {+0.02/11}
c5 {+1.40/12} 12. Nb3 {-0.06/12} Nxc4 {+1.29/13} 13. Nxc5 {-0.01/11}
Na5 {+1.29/13} 14. Rd1 {+0.00/11} Qb6 {+1.20/13} 15. b4 {-0.01/12}
dxc5 {+1.22/13} 16. bxa5 {-0.16/12} Qxa5 {+1.16/12} 17. Qb2 {-0.22/11}
h6 {+1.12/11} 18. Bf4 {+0.00/9} b6 19. Rd6 {-0.12/11} Be6 {+1.47/11} 20.
Rad1 {-0.11/10} Qa4 {+1.46/11} 21. R1d2 {-0.31/10} Rac8 {+1.61/11} 22.
h4 {-0.37/10} b5 {+1.84/11} 23. Qc1 {-0.40/10} Nh5 {+1.90/11} 24.
Be3 {-0.40/12} f5 {+1.84/12} 25. Qb2 {-0.25/10} Nf6 {+1.89/12} 26.
Bf4 {-0.13/10} Qc4 {+1.82/12} 27. e3 {-0.23/12} Qa4 {+1.53/11} 28.
Bf1 {-0.24/12} a6 {+1.46/12} 29. c4 {+0.22/12} Bxc4 {+1.27/12} 30.
Rxf6 {+3.89/11} gxf6 {-2.31/12} 31. Qxf6 {+5.01/10} Re6 {-4.33/12} 32.
Qxf5 {+5.06/10} Rce8 {-7.77/12} 33. Rd7 {+320.00/9} R8e7 {-99.83/11} 34.
Rd8+ {+320.00/5}
{Black resigns} 1-0

Guenther