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Up Topic The Rybka Lounge / Test Positions / 9 troublemakers from Der brillante Schachzug
- - By dcorbit (***) [us] Date 2010-06-15 18:23
I am looking for a mechanical score to all of the 'Der brillante Schachzug' positions, and I have solved all but 9.
At the end of each position, I have added my calculated pv and ce.

1rr1b1k1/1pq1bp2/p2p1np1/4p3/P2BP3/2NB2Q1/1PP3PP/4RR1K w - - bm Rxf6; id "
Der brillante Schachzug (009) - Siz. Qualit├Ątsopfer"; pv Ba7 Ra8 Be3 Qd8 Qf3 b5 Bg5 b4 Bxf6 bxc3 b3 Bxf6 Qxf6 Qxf6 Rxf6 Rc6 Bc4 Kg7 Ref1 Rxc4 bxc4; ce 109;
2K5/8/8/2P4n/8/8/1Npk3B/8 w - - bm c6; id "
Der brillante Schachzug (011) - L&S vs S"; pv c6 c1=Q; ce -696;
nk1b4/2rPp3/4Q1p1/1K2Br2/5P2/8/1P6/8 w - - bm Ka6; id "
Der brillante Schachzug (015) - Zugzwang"; pv b4 Rxe5+ Qxe5 Ka7 Qe3+ Kb8 Qe5; ce 0;
5nr1/2Pp2pk/3Pp1p1/4P1P1/6P1/5K2/8/7n w - - bm c8=N; id "
Der brillante Schachzug (024) - Zugzwang"; pv Kg2 Rh8 Kxh1 Kg8+ Kg2 Rh4 Kg3 Rh1 c8=Q Kf7 Qc5 Rb1 Qf2+ Ke8 Qd4 Kf7 Kf4 Nh7 Ke3 Re1+; ce 214;
3k4/8/3N4/P7/6pb/8/6P1/2K1n3 w - - bm Nf7+; id "
Der brillante Schachzug (033) - S&B vs L&S"; pv a6 Bf2 Ne4 Ba7 Nf6 Nd3+ Kd2 Ne5 Kc3 Ke7 Nd5+ Kd6 Nf4 Kc6 Ne6 Kb5 Nf4 Kxa6 Nd3 Nxd3 Kxd3 g3 Kc4 Kb6 Kd3 Kc6 Ke2 Kd5 Ke1 Bf2+ Kd2 Ke4 Ke2 Be3 Kd1 Kd3 Ke1 Bd2+ Kf1 Ke3 Kg1 Ke2 Kh1 Bc3 Kg1 Bd4+ Kh1 Bf6 Kg1 Be5 Kh1 Bf4 Kg1 Bd6 Kh1 Bf8 Kg1 Bc5+ Kh1 Bd4; ce -569;
4Q3/4n1r1/6Pp/1B6/8/8/6r1/5K1k w - - bm a5a6; id "
Der brillante Schachzug (035) - D&L vs T&T&S"; pv a5a6 Bh4f2 g2g3 Ne1f3 Kc1d1 Nf3e5; ce -577;
3k4/2pq3p/pp5R/4P3/P6P/2PN4/1PN3K1/8 w - - bm Nd4; id "
Der brillante Schachzug (053)"; pv Kf3 Qxd3+ Ne3 Qb1 Kf4 Qxb2 Rxh7 Qf2+ Ke4 Qa2 Rh8+ Kd7 h5 Qxa4+ Kf5 Qa2 Ng4 Qb1+ Kf6 Qf1+ Kg5 Ke7 h6 Qc1+ Kh5 Qh1+ Kg5 Kf7 Rh7+ Ke6 Rxc7 Qc1+ Kg6 Qb1+ Kh5 Qh1+ Kg5; ce 0;
2r1r1k1/4bppp/1q4n1/3pP3/p1pP4/PnR2NBP/1P4P1/1B1QR2K w - - bm Nb2c4+; id "
Der brillante Schachzug (057)"; pv Nb2c4+ Kd2e2 c5c6 c2c1Q c6c7 Qc1xc4 Bh2e5 Qc4b3 Kc8d8 Qb3d5+ Kd8c8 Ke2e3 Kc8b8 Qd5xe5 Kb8a8 Qe5d5+ Ka8b8 Qd5b5+ Kb8a8 Qb5c6+ Ka8b8 Qc6d6 Kb8b7 Qd6b4+ Kb7a7 Qb4c3 Ka7b7 Qc3b3+ Kb7c6 Qb3c2+ Kc6b7 Qc2b1+ Kb7a7 Qb1f5 Ka7b7 Qf5f3+ Kb7b8 Qf3f4 Kb8b7 Qf4e4+ Kb7a; ce -923;
1rbr2k1/4q1p1/p2bp2p/8/R6P/3QB1P1/4PPB1/2R3K1 w - - bm Bxh6; id "
Der brillante Schachzug (064)"; pv Rg4 Rb4 Qg6 Rxg4 Qxg4 Qf6; ce 177;
Parent - - By CSullivan (**) [us] Date 2010-06-19 15:59
Hi Dann,
I'm willing to at least look at these positions.  What is "ce"?  Is there someplace I can get more English-language information on this?
Thanks,
Charles
Parent - - By yanquis1972 (****) [us] Date 2010-06-19 21:33
as i posted on talkchess, rybka solved position #1 fairly easily on my run (i think around 30 minutes, 4cores @ 3ghz).  in mpv it solved it much quicker. 

i haven't tried any of the endgame ones & R4 didn't solve the last position on my run.
Parent - - By yanquis1972 (****) [us] Date 2010-06-20 00:23
R4 unable to find Bxh6 through d25. i saved the hash so i may give it another go. something's wrong with the position above it; hopefully dann will correct it.
Parent - By Dadi Jonsson (Silver) [is] Date 2010-06-20 11:07

> something's wrong with the position above it


This is the correct position (#57), but the key move is 1.e6.
Parent - - By Dadi Jonsson (Silver) [is] Date 2010-06-20 11:42
"ce" is the engine evaluation in centipawns. The "bm" at the end of the string above the diagrams shows the "best move".
Parent - By CSullivan (**) [us] Date 2010-06-26 23:36
Thanks, Dadi!  (And thanks for the correction regarding #59.)
Charles
Parent - - By CSullivan (**) [us] Date 2010-06-26 23:55
Regarding Der brillante Schachzug (#59):
2r1r1k1/4bppp/1q4n1/3pP3/p1pP4/PnR2NBP/1P4P1/1B1QR2K w - - bm e6;

Sad to say, after almost 27 hours (28 complete iterations), the best from Rybka3 (4cores/Q6600/3GHz/1GB) is 1.Bf5 Nf8 2.Bxc8 Rxc8 3.Rf1 Ne6 4.Bf2 Bd8 5.Nd2 Nxd2 6.Qxd2 Rb8 7.Rc2 Bg5 8.Be3 h6 9.Bxg5 Nxg5 10.Qf4 Rf8 11.Re1 Ne6 12.Qe3 Ng5 13.Ree2; ce +63

However, if I force 1.e6!, then Rybka3 shows +1.07 after 20 hours (25 plies) and +1.20 after 28:35:55 (26 plies) and after 46:50:23 (ply 27) finally displays a PV:
1...f6 2.Nh4 Nxh4 3.Bxh4 f5 4.Bxf5 Qxd4 5.Bxe7 Qxd1 6.Rxd1 d4 7.Bb4 dxc3 8.e7 c2 9.Bxc2 g6 10.Re1 Kg7 11.Kh2 Rc7 12.Bd1 Kf6 13.Rf1+ Ke5 14.Rf7 Kd4 15.Rxh7 Nc5 16.Rh4+ Kd3; ce +120

Obviously, this would be an interesting test for Rybka4 or Cluster Rybka.

Charles
Parent - - By dcorbit (***) [us] Date 2010-06-28 18:37
Thank you very much for this analysis.  I may give Rybka 4 a very long run and see what happens.
Parent - By dcorbit (***) [us] Date 2010-06-29 18:39
I only had time for a 12 hour run, but Rybka 4 with 4 CPUs at 3 GHz and 1 GB hash did not find it.
Analysis from Q:\DerBrillanteSchachzug59.epd  
6/28/2010 10:20:00 PM Level: 43200 Seconds
Analyzing engine: Deep Rybka 4 x64

1) e6; id "Der brillant
    Searching move: e5-e6
    Best move (Deep Rybka 4 x64): Bb1-f5
    Not found in: 12:00:00
      2+  00:01           201  207  +0.39  Bb1f5 Rc8c6 Bf5d7
      2+  00:01           229  229  +0.52  Bb1f5 Rc8c6 Bf5d7
      2  00:01           290  290  +0.52  Bb1f5 Rc8d8 e5e6 f7xe6 Re1xe6 Qb6b5
      3  00:01           952  846  +0.22  Bb1f5 Rc8d8 Kh1h2 f7f6 Re1f1 f6xe5
      4+  00:01         1.510  1.289  +0.34  Bb1f5 Rc8d8 Rc3e3
      4  00:01         1.576  1.345  +0.27  Bb1f5 Rc8d8 Rc3e3 Qb6c7 Qd1c2
      5  00:01         2.551  2.094  +0.36  Bb1f5 Rc8d8 Rc3e3 Qb6c7 Qd1c2 Rd8b8 Kh1g1 Re8d8
      6  00:01         6.964  5.648  +0.14  Bb1f5 Rc8d8 Rc3e3 Ng6f8 e5e6 f7xe6 Bf5xe6+ Nf8xe6 Re3xe6 Qb6b7 Qd1e2 Rd8d7 Bg3e5
      7+  00:01         9.438  7.556  +0.26  Bb1f5 Rc8d8 Rc3e3 Ng6f8 e5e6 f7xe6 Bf5xe6+ Nf8xe6 Re3xe6 Qb6b7 Qd1e2 Rd8d7 Bg3e5 Rd7d8
      7  00:01        13.980  11.060  +0.28  Bb1f5 Rc8d8 Rc3e3 Kg8h8 e5e6 f7f6 Kh1g1 Be7d6 Bg3xd6 Rd8xd6 e6e7 Ng6f4 Kg1f2
      8  00:01        30.637  23.087  +0.31  Bb1f5 Rc8d8 Rc3e3 Qb6a7 e5e6 f7f6 Kh1h2 Be7d6 Bg3xd6 Rd8xd6 Bf5xg6
      9  00:02        36.532  26.588  +0.31  Bb1f5 Rc8d8 Rc3e3 Qb6a7 e5e6 f7f6 Kh1h2 Be7d6 Bg3xd6 Rd8xd6 Bf5xg6
     10  00:02       105.480  65.597  +0.23  Bb1f5 Rc8d8 Rc3e3 Qb6a7 Kh1g1 Ng6f8 e5e6 f7xe6 Bf5xe6+ Nf8xe6 Re3xe6 Rd8d7 Bg3e5 Kg8f7 Be5f4 Kf7g8
     11  00:02       205.220  103.541  +0.31  Bb1f5 Rc8d8 Rc3e3 Qb6a7 Kh1g1 Ng6f8 e5e6 f7xe6 Bf5xe6+ Nf8xe6 Re3xe6 Rd8d7 Bg3e5 Qa7a5 Qd1c2 g7g6 Be5f4
     12  00:02       285.472  124.442  +0.30  Bb1f5 Rc8d8 Rc3e3 Qb6a7 Kh1g1 Qa7b7 e5e6 f7f6 Bg3h2 Be7d6 Qd1c2 Bd6xh2+ Kg1xh2 Qb7b6 Bf5xg6 h7xg6 e6e7 Rd8c8 Qc2xg6 Nb3xd4 Nf3xd4
     13  00:04       761.166  194.373  +0.20  Bb1f5 Rc8a8 Rc3e3 Ng6f8 e5e6 f7f6 Bg3f2 Nf8g6 Re3c3 Be7d6 Qd1c2 Bd6f4 g2g3 Bf4c7 Kh1g2 Re8e7 Kg2g1
     14  00:09     2.198.645  243.806  +0.21  Bb1f5 Rc8d8 Rc3e3 Qb6a7 Kh1g1 Kg8h8 e5e6 f7f6 Kg1h2 Be7d6 Bf5xg6 h7xg6 Nf3h4 Bd6xg3+ Re3xg3 Nb3xd4 Nh4xg6+ Kh8g8 e6e7 Rd8b8 Rg3g4 Qa7c7+
     15  00:17     4.527.430  265.507  +0.11  Bb1f5 Rc8d8 Rc3e3 Ng6f8 e5e6 f7f6 h3h4 g7g6 Bf5h3 f6f5 h4h5 Rd8c8 Kh1h2 Rc8c6
     16  00:34     9.267.552  271.258  +0.08  Bb1f5 Rc8d8 Rc3e3 Ng6f8 e5e6 f7f6 Bg3h2 Kg8h8 Bh2f4 Kh8g8 Bf4g3 Rd8a8 Re1e2 Nf8g6 Bf5c2 Be7d6 Bg3xd6 Qb6xd6 Bc2xg6 h7xg6 e6e7 Qd6f4
     17+  00:41    11.043.859  273.119  +0.20  Bb1f5 Rc8d8 e5e6 f7f6 Bg3f2 Be7d6 Bf5xg6 h7xg6 Nf3h4 g6g5 Nh4f5 g7g6 Nf5h6+ Kg8g7 Nh6f7 Rd8c8 Qd1f3 Qb6c6
     17+  00:47    12.655.148  269.235  +0.35  Bb1f5 Rc8d8 e5e6 f7f6 Bg3f2 Be7d6 Bf5xg6 h7xg6 Nf3h4 g6g5 Nh4f5 g7g6 Nf5h6+ Kg8g7 Nh6f7 Rd8c8 Qd1f3 Qb6c6
     17  00:51    13.586.644  267.564  +0.38  Bb1f5 Rc8d8 e5e6 f7f6 Nf3h4 Nb3xd4 Bf5xg6 h7xg6 Bg3f2 Be7c5 e6e7 Rd8d6 Nh4xg6 Nd4b5 Bf2xc5 Nb5xc3 Qd1d4 Nc3b5 Bc5xb6 Nb5xd4 Bb6xd4 Kg8f7 Ng6f4 Rd6d7 Re1d1 Re8xe7 Rd1d2 Re7e8 Kh1h2 Re8b8 Kh2g1
     18  01:13    19.570.562  267.770  +0.49  Bb1f5 Ng6f8 Bf5xc8 Re8xc8 Bg3f2 Nf8e6 Re1f1 Rc8b8 Bf2e3 Be7d8 Qd1c2 Qb6a7 Qc2f2 Bd8a5 Rc3c2 Ba5b6 Rf1d1 h7h6 Kh1g1
     19  02:11    33.946.166  259.511  +0.50  Bb1f5 Ng6f8 Bf5xc8 Re8xc8 Bg3f2 Nf8e6 Bf2e3 Rc8b8 Qd1c2 Qb6a7 Re1d1 Qa7a5 Rd1f1 h7h6 Kh1g1 Qa5b6 Qc2f5 g7g6 Qf5c2
     20  02:33    39.541.415  259.408  +0.50  Bb1f5 Ng6f8 Bf5xc8 Re8xc8 Bg3f2 Nf8e6 Bf2e3 Rc8b8 Qd1c2 Qb6a7 Re1d1 Qa7a5 Rd1f1 h7h6 Kh1g1 Qa5b6 Qc2f5 g7g6 Qf5c2 Ne6xd4 Qc2f2 Nd4xf3+
     21  05:16    82.707.290  261.450  +0.52  Bb1f5 Ng6f8 Bf5xc8 Re8xc8 Bg3f2 Nf8e6 Bf2e3 Rc8b8 Qd1c2 Rb8f8 Re1f1 f7f5 e5xf6/ep Be7xf6 Qc2d1 Rf8b8 Rc3c2 Rb8e8 Rc2e2 Re8c8 Rf1e1 Rc8b8 Be3f2 Nb3xd4 Qd1xa4
     22  06:57   109.514.054  263.012  +0.52  Bb1f5 Ng6f8 Bf5xc8 Re8xc8 Bg3f2 Nf8e6 Bf2e3 Rc8b8 Qd1c2 Rb8f8 Re1f1 f7f5 e5xf6/ep Be7xf6 Qc2d1 Rf8d8 Rc3c2 Rd8e8 Rc2e2 Re8c8 Re2e1 Rc8d8 Be3f2 Ne6xd4 Nf3xd4 Bf6xd4
     23  15:00   240.395.344  267.133  +0.55  Bb1f5 Ng6f8 Bf5xc8 Re8xc8 Bg3f2 Nf8e6 Bf2e3 Rc8b8 Qd1c2 Qb6a7 Qc2f2 Nb3a5 Re1d1 Na5c6 Rc3c2 Rb8b3 Nf3d2 Rb3d3 Rc2c3 Rd3xc3 b2xc3 Be7xa3 Qf2f3 Qa7d7
     24  30:56   491.753.979  265.019  +0.58  Bb1f5 Ng6f8 Bf5xc8 Re8xc8 Bg3f2 Nf8e6 Bf2e3 Rc8b8 Qd1c2 Qb6a7 Qc2f2 Be7d8 Re1d1 Nb3a5 Rc3c2 Na5b3 Nf3h4 g7g6 Nh4f3 Bd8b6
     25  54:49   862.793.683  262.369  +0.59  Bb1f5 Ng6f8 Bf5xc8 Re8xc8 Bg3f2 Nf8e6 Bf2e3 Rc8b8 Re1f1 Qb6a7 Rc3c2 Be7d8 Qd1e1 Bd8b6 Qe1h4 h7h6 Rf1d1 Rb8e8 Qh4g4 Kg8h8 Rc2f2 Re8d8 Qg4h4
     26  1:26:48  1.451.158.353  278.656  +0.59  Bb1f5 Ng6f8 Bf5xc8 Re8xc8 Bg3f2 Nf8e6 Bf2e3 Rc8b8 Re1f1 Qb6a7 Rc3c2 Be7d8 Qd1e1 Bd8b6 Qe1h4 h7h6 Rf1d1 Rb8e8 Qh4g4 Kg8h8 Rc2f2 Re8d8 Qg4h4
     27  2:01:56  2.056.163.790  281.047  +0.59  Bb1f5 Ng6f8 Bf5xc8 Re8xc8 Bg3f2 Nf8e6 Bf2e3 Rc8b8 Re1f1 Qb6a7 Rc3c2 h7h6 Qd1e1 Be7d8 Qe1g3 Bd8b6 Rc2f2 Rb8b7 Rf1d1 Kg8h8 Qg3h4 Kh8g8 Qh4g4 Kg8h8
     28  5:40:46  5.488.707,647  268.455  +0.64  Bb1f5 Ng6f8 Bf5xc8 Re8xc8 Re1f1 Nf8e6 Bg3e1 Be7d8 Rc3c2 Rc8b8 Be1c3 h7h6 Rc2f2 Rb8b7 Qd1c2 Qb6a7 Rf1d1 Rb7b8 Qc2f5 g7g6 Qf5g4 h6h5 Qg4g3 Bd8b6 Qg3h4
     29  8:03:27  8.052.876,096  277.621  +0.64  Bb1f5 Ng6f8 Bf5xc8 Re8xc8 Re1f1 Nf8e6 Bg3e1 Be7d8 Rc3c2 Rc8b8 Be1c3 h7h6 Rc2f2 Rb8b7 Qd1c2 Qb6a7 Rf1d1 Rb7b8 Qc2f5 Bd8b6 Qf5g4 Kg8h7 Rf2f1 Rb8b7 Qg4h4
   6/29/2010 10:20:07 AM, Time for this analysis: 12:00:00, Rated time: 12:00:00

0 of 1 matching moves
6/29/2010 10:20:08 AM, Total time: 12:00:08 PM
Rated time: 12:00:00 = 43200 Seconds
Parent - - By CSullivan (**) [us] Date 2010-06-29 19:29
You're welcome.  By the way, further analysis has shown me that after 1.e6 f6, Black is lost.  On the other hand, 1...Bf6 seems to lead to an endgame in which Black has drawing chances, despite a 2-pawn deficit.
Charles
Parent - - By dcorbit (***) [us] Date 2010-06-29 19:50
I would be very keen to see this analysis
Parent - By CSullivan (**) [us] Date 2010-06-30 02:34
You asked for it....:smile:
Der brillante Schachzug  #57  [not #59 -- what was I thinking??]
2r1r1k1/4bppp/1q4n1/3pP3/p1pP4/PnR2NBP/1P4P1/1B1QR2K w - - bm e6; id "

(Warning: I have not checked the following analysis with multiple computers, but I have spent about 48 hours getting to move 41.  Long variation--wrong variation!)

1.e6 Bf6 2.exf7+ Kxf7 3.Ne5+ Kg8 4.Nxg6 Rxe1+ 5.Bxe1 hxg6 6.Qg4 Re8 7.Bf2 Nd2! (7...Nxd4 soon becomes untenable) 8.Bxg6 Ne4 9.Be1 Qe6 10.Bxe8 Qxe8 11.Rf3 Bxd4 12.Qf5 Be5 13.Bc3 Ng3+ 14.Rxg3 Bxg3 15.Qg4 d4 16.Bxd4 Qe1+ 17.Bg1 Be5 18.Qxc4+ Kh8 19.Qc6 Qa5 20.Qd7 Kh7 21.Qd3+ Kh8 22.Qe2 Kh7 23.Qe4+ Kg8 24.Qc4+ Kh8 25.Qc8+ Kh7 26.Qf5+ Kg8 27.Qe6+ Kh7 28.Qe8 Bf6 29.Qe4+ Kh8 30.Bd4 Qd2 31.Be5 Bxe5 32.Qxe5 Qf2 33.Qe8+ Kh7 34.Qe4+ Kh8 35.Qe5 Kh7 36.Kh2 Kh6 37.Qe6+ g6 38.Qe5 Kh7 39.Qc7+ Kh6 40.Qc1+ Kh7 41.Qc3
8/7k/6p1/8/p7/P1Q4P/1P3qPK/8 b - -

It looks like White should win this, but he must be careful not to allow a perpetual check.  I've carried the analysis quite a bit further, but I'm not convinced that White has a forced win....
Charles
Parent - - By CSullivan (**) [us] Date 2010-06-29 19:25
Regarding Der brillante Schachzug #53:
3k4/2pq3p/pp5R/4P3/P6P/2PN4/1PN3K1/8 w - - bm Nd4; id "

The given solution begins 1.Nd4 Qg7+ 2.Kh3 Qxh6 3.Nf4 Kc8 4.Nde6 Kb7 5.h5 c5 6.Kg4
8/1k5p/pp2N2q/2p1P2P/P4NK1/2P5/1P6/8 b - -


Now, 6...c4 7.Kf3 Kc6 8.Ke4 b5 9.axb5+ axb5 10.Kd4 Kb6 11.Kd5 is, in fact, won.  For example: 11...Ka6 12.Kc6 Ka5 13.Kb7 b4 14.Kc6 bxc3 15.bxc3 Ka4 16.Kd5 Kb5 17.Kd4, and White picks up the c-pawn with an easy win.

However, after 6...Kc6! 7.Kf3 b5!, Black gets enough counterplay on the queenside to hold the draw (IMHO).  One nice line is 8.a5 (8.axb5 Kxb5! also works) 8...c4! 9.Ke4 b4! 10.cxb4 Kb5
8/7p/p3N2q/Pk2P2P/1Pp1KN2/8/1P6/8 w - -
Parent - - By Kornrade (*) [ro] Date 2010-07-12 22:09 Edited 2010-07-12 22:13
White is winning in your variation as well, but with correct play. Here is a sample variation of correct play (the idea is to keep the c-pawn on the c-file)

9. Ke4 b4 10. Kd4! (instead of 10.cxb4?) Kb5 11. Kd5 bxc3 12. bxc3 Kxa5 13. Kxc4
Kb6 (13... Ka4 14. Kd5) 14. Kd5 a5 15. c4 a4 16. c5+ Ka6 17. Kc4 Ka5 18. c6 Kb6
19. c7 Kb7 20. Kb4 Kc8 21. Kxa4 Kd7 22. Kb5 Kc8 23. Kc6 winning by zugzwang
Parent - By CSullivan (**) [us] Date 2010-07-17 02:40

> White is winning in your variation as well, but with correct play.


You are absolutely correct.  I feel humbler than usual!
Charles
Parent - By CSullivan (**) [us] Date 2010-06-30 00:12
Regarding Der brillante Schachzug #35
4Q3/4n1r1/6Pp/1B6/8/8/6r1/5K1k w - - bm Bc6; id "


Zappa Mexico II (with null move disabled) gives (a) mate in 33 after 1 min 19 seconds: 1.Bc6 Nxc6 2.Qe3 Kh2 3.Qxh6+ Kg3 4.Qg5+ Kf3 5.Qxg2+ Kf4 6.Qxc6 and
(b) mate in 23 after 9 minutes 54 seconds: 1.Bc6 Nxc6 2.Qe3 Kh2 3.Qxh6+ Kg3 4.Qxg7 Rf2+ 5.Ke1 Kg2 6.Qb7 Rf1+, etc.  Although the given solution is a mate-in-9, I believe that best play on both sides is mate  in 22.
Parent - - By CSullivan (**) [us] Date 2010-07-04 15:41
Regarding Der brillante Schachzug #15:
nk1b4/2rPp3/4Q1p1/1K2Br2/5P2/8/1P6/8 w - - bm Ka6; id "

With null move disabled, Zappa Mexico II (Q6600/4cpu/3GHz/1GB hash) finds, on the 22nd iteration after 4 hours 24 minutes, the winning line: 1.Ka6 Rf6 2.f5 gxf5 3.Qxf6 exf6 4.Bf4 Be7 5.b3, etc., with mate in 25 (I think a mate in 23 is best play).

Rybka3 (4cpu/1GB hash) fails after 7.5 hours and33 iterations, giving 1.Qb3 Kb7 (0.00).
Even when I force 1.Ka6 Rf6, Rybka3 cannot find the correct variation after 36 iterations, instead giving 2.f5 gxf5 3.Qxf6 exf6 4.Bf4 Be7 5.b4?
Parent - - By dcorbit (***) [us] Date 2010-07-12 19:16
Thank you for this analysis
Parent - By CSullivan (**) [us] Date 2010-07-17 02:44
You're welcome.  It appears that all the given solutions are correct, except possibly for #57 (which was not a composed problem).
Charles
Up Topic The Rybka Lounge / Test Positions / 9 troublemakers from Der brillante Schachzug

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