Author: John Merlino
Date: 11:25:51 04/13/05
Go up one level in this thread
On April 13, 2005 at 12:24:40, pavel wrote: >[D] 3n4/rBp1p3/2P5/2PK4/k2N4/pp2R3/bppB2Rp/q1n1r1b1 w - - 0 1 > >Mate in 29 >M. Kwiatkowski >2nd Honourable Mention, The Problemist 1992 > >1.Rg4 Even if it threatens two short mates, with Nxb3+ and Ne6+, it is still a >nice key. 1...h1Q+ 2.Nf3+ Kb5 Now the Knight and Rook each have chores, but they >can only do them if they work as a fine-tuned team - one of them holding the Qh1 >at bay, while the other one does its job. 3.Rb4+ Ka5 4.Rbe4+! Now the Knight is >free. 4...Kb5 5.Nd4+ Ka4 6.Ne2+ Kb5 7.Nc3+ Ka5 8.Nxa2+ Why this Bishop had to go >will become clear later. 8...Kb5 Now it is the Rook's turn, but the Knight must >first unpin it. 9.Nc3+ Ka5 10.Ne2+ Kb5 11.Nd4+ Ka4 12.Nf3+! Kb5 13.Rb4+ Ka5 >14.Rbxb3+ The reason for removing this pawn will be revealed later too, but at >least we understand why the Ba2 had to go - it would have pinned the Rb3. >14...Ka4 15.Rb4+ Ka5 16.Rbe4+! and the Knight is unpinned once more. 16...Kb5 >17.Nd4+ Ka4 18.Ne2+ Kb5 19.Nc3+ Ka5 20.Na2+! It is a very nice feature of this >problem that the Knight goes back to the empty square a2 where it once captured >a Bishop. Now, it has to shield a3 from the Qa1. 20...Kb5 21.Ba6+ Finally, the >mating attack. 21...Rxa6 If 21...Kxa6, then 22.Rxa3+ (that is why Pb3 had to go >and Qxa3 had to be prevented) 22...Kb5 23.Nc3 mate. 22.Nc3+ Ka5 23.Ne2+ Kb5 >24.Nd4+ Ka4 25.Nf3+! One last unpin of the Rook, and it's mate: 25...Kb5 26.Rb4+ >Ka5 27.Rb6+ Ka4 28.Rxa6+ Kb5 29.Ra5 mate. > >http://www.xs4all.nl/~timkr/chess2/diarytxt.htm > >--------------------------------------------------------- > >So far with Shredder Classic 1.2 > >New game >3n4/rBp1p3/2P5/2PK4/k2N4/pp2R3/bppB2Rp/q1n1r1b1 w - - 0 1 > >Analysis by Shredder Classic 1.2: > >1.Bxe1 > -+ (-31.21) Depth: 1/8 00:00:00 >1.Bxe1 > -+ (-31.21) Depth: 1/8 00:00:00 >1.Rg4 > = (0.14) Depth: 1/8 00:00:00 >1.Rg4 > = (0.14) Depth: 1/8 00:00:00 >1.Rg4 h1Q+ > = (0.14) Depth: 2/8 00:00:00 >1.Rg4 h1Q+ > = (-0.11) Depth: 3/8 00:00:00 >1.Rg4 h1Q+ > ³ (-0.61) Depth: 3/8 00:00:00 >1.Rg4 h1Q+ 2.Nf3+ Kb5 > -+ (-37.04) Depth: 3/11 00:00:00 >1.Bxe1 > -+ (-37.03) Depth: 3/11 00:00:00 >1.Bxe1 > -+ (-36.68) Depth: 3/11 00:00:00 >1.Bxe1 h1Q 2.Nxc2 > -+ (-36.16) Depth: 3/13 00:00:00 >1.Rxe1 > -+ (-36.15) Depth: 3/13 00:00:00 >1.Rxe1 > -+ (-35.80) Depth: 3/13 00:00:00 >1.Rxe1 e6+ 2.Rxe6 b1Q > -+ (-31.69) Depth: 3/13 00:00:00 >1.Rxe1 e6+ > -+ (-32.00) Depth: 4/16 00:00:00 >1.Rxe1 b1Q 2.Rgxg1 > -+ (-32.00) Depth: 4/16 00:00:00 >1.Rxe1 b1Q > -+ (-32.45) Depth: 5/16 00:00:00 >1.Rxe1 h1Q 2.Rexg1 Qh5+ 3.Rg5 Qf7+ 4.Ke4 > -+ (-32.79) Depth: 5/16 00:00:00 >1.Rxe1 h1Q 2.Rexg1 Qh5+ 3.Rg5 Qf7+ 4.Ke4 b1Q > -+ (-32.79) Depth: 6/23 00:00:00 39kN >1.Rg4 > -+ (-32.78) Depth: 6/25 00:00:00 92kN >1.Rg4 > -+ (-32.43) Depth: 6/29 00:00:01 102kN >1.Rg4 h1Q+ 2.Nf3+ Kb5 3.Rb4+ Ka5 4.Rg4+ Kb5 5.Rb4+ Ka5 6.Rg4+ Kb5 > = (0.04) Depth: 6/29 00:00:01 117kN >1.Rg4 h1Q+ 2.Nf3+ Kb5 3.Rb4+ Ka5 4.Rbe4+ Kb5 5.Nd4+ Ka4 > = (0.06) Depth: 7/29 00:00:01 128kN >1.Rg4 h1Q+ 2.Nf3+ Kb5 3.Rb4+ Ka5 4.Rbe4+ Kb5 5.Nd4+ Ka4 > = (0.06) Depth: 8/29 00:00:01 160kN >1.Rg4 h1Q+ 2.Nf3+ Kb5 3.Rb4+ Ka5 4.Rbe4+ Kb5 5.Nd4+ Ka4 > = (0.06) Depth: 9/29 00:00:02 307kN >1.Rg4 h1Q+ 2.Nf3+ Kb5 3.Rb4+ Ka5 4.Rbe4+ Kb5 5.Nd4+ Ka4 > = (0.06) Depth: 10/29 00:00:04 653kN >1.Rg4 h1Q+ 2.Nf3+ Kb5 3.Rb4+ Ka5 4.Rbe4+ Kb5 5.Nd4+ Ka4 > = (0.08) Depth: 11/29 00:00:05 1744kN >1.Rg4 h1Q+ 2.Nf3+ Kb5 3.Rb4+ Ka5 4.Rbe4+ Kb5 5.Nd4+ Ka4 > = (0.10) Depth: 12/29 00:00:08 4533kN >1.Rg4 h1Q+ 2.Nf3+ Kb5 3.Rb4+ Ka5 4.Rbe4+ Kb5 5.Nd4+ Ka4 > = (0.10) Depth: 13/29 00:00:18 10715kN >1.Rg4 h1Q+ 2.Nf3+ Kb5 3.Rb4+ Ka5 4.Rbe4+ Kb5 5.Nd4+ Ka4 > = (0.12) Depth: 14/29 00:00:37 23338kN >1.Rg4 h1Q+ 2.Nf3+ Kb5 3.Rb4+ Ka5 4.Rbe4+ Kb5 5.Nd4+ Ka4 > = (0.14) Depth: 15/29 00:01:23 51452kN >1.Rg4 h1Q+ 2.Nf3+ Kb5 3.Rb4+ Ka5 4.Rbe4+ Kb5 5.Nd4+ Ka4 > = (0.14) Depth: 16/31 00:03:20 112629kN >1.Rg4 h1Q+ 2.Nf3+ Kb5 3.Rb4+ Ka5 4.Rbe4+ Kb5 5.Nd4+ Ka4 > = (0.15) Depth: 17/32 00:07:17 241546kN >1.Rg4 h1Q+ 2.Nf3+ Kb5 3.Rb4+ Ka5 4.Rbe4+ Kb5 5.Nd4+ Ka4 > = (0.15) Depth: 18/35 00:15:11 507078kN >1.Rg4 h1Q+ 2.Nf3+ Kb5 3.Rb4+ Ka5 4.Rbe4+ Kb5 5.Nd4+ Ka4 > = (0.15) Depth: 19/38 00:33:03 1090950kN >1.Rg4 h1Q+ 2.Nf3+ Kb5 3.Rb4+ Ka5 4.Rbe4+ Kb5 5.Nd4+ Ka4 > = (0.15) Depth: 20/41 01:13:32 2366093kN > >(, MyTown 13.04.2005) The King cannot find this mate from the initial position because it has a search depth of (I think) 47 plies. So, just move the position forward to after 6.Ne2+, and The King says "Mate in 23" in less than a second: [D]3n4/rBp1p3/2P5/2PK4/k3R3/pp2R3/bppBN3/q1n1r1bq b - - 0 6 Time Depth Score Positions Moves 0:00 1/3 0.00 903 6...Kb5 7.Nd4+ 0:00 1/4 0.00 5096 6...Kb5 7.Nd4+ 0:00 1/5 0.00 16935 6...Kb5 7.Nd4+ 0:00 1/6 0.00 50798 6...Kb5 7.Nd4+ 0:00 1/7 Mate23 163463 6...Kb5 7.Nc3+ Ka5 8.Nxa2+ Kb5 9.Nc3+ Ka5 10.Ne2+ Kb5 11.Nd4+ Ka4 12.Nf3+ Kb5 13.Rb4+ Ka5 14.Rbxb3+ Ka4 15.Rb4+ Ka5 16.Rbe4+ Kb5 17.Nd4+ Ka4 18.Ne2+ Kb5 19.Nc3+ Ka5 20.Na2+ Kb5 21.Ba6+ Rxa6 0:01 1/8 Mate23 479548 6...Kb5 7.Nc3+ Ka5 8.Nxa2+ Kb5 9.Nc3+ Ka5 10.Ne2+ Kb5 11.Nd4+ Ka4 12.Nf3+ Kb5 13.Rb4+ Ka5 14.Rbxb3+ Ka4 15.Rb4+ Ka5 16.Rbe4+ Kb5 17.Nd4+ Ka4 18.Ne2+ Kb5 19.Nc3+ Ka5 20.Na2+ Kb5 21.Ba6+ Rxa6 0:03 1/9 Mate23 1274599 6...Kb5 7.Nc3+ Ka5 8.Nxa2+ Kb5 9.Nc3+ Ka5 10.Ne2+ Kb5 11.Nd4+ Ka4 12.Nf3+ Kb5 13.Rb4+ Ka5 14.Rbxb3+ Ka4 15.Rb4+ Ka5 16.Rbe4+ Kb5 17.Nd4+ Ka4 18.Ne2+ Kb5 19.Nc3+ Ka5 20.Na2+ Kb5 21.Ba6+ Rxa6 0:10 1/10 Mate23 3425030 6...Kb5 7.Nc3+ Ka5 8.Nxa2+ Kb5 9.Nc3+ Ka5 10.Ne2+ Kb5 11.Nd4+ Ka4 12.Nf3+ Kb5 13.Rb4+ Ka5 14.Rbxb3+ Ka4 15.Rb4+ Ka5 16.Rbe4+ Kb5 17.Nd4+ Ka4 18.Ne2+ Kb5 19.Nc3+ Ka5 20.Na2+ Kb5 21.Ba6+ Rxa6 Also notice that The King will not report a PV longer than 31 plies, which is why the full mate sequence is not shown. jm
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.