Hard Puzzles found on Gameknot

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MikeGL
Posts: 958
Joined: Thu Sep 01, 2011 12:49 pm

Re: Hard Puzzles found on Gameknot

Post by MikeGL » Sun Jun 21, 2020 2:54 pm

+M25


I told my wife that a husband is like a fine wine; he gets better with age. The next day, she locked me in the cellar.

Vinvin
Posts: 4752
Joined: Thu Mar 09, 2006 8:40 am
Full name: Vincent Lejeune

Re: Hard Puzzles found on Gameknot

Post by Vinvin » Sun Jun 21, 2020 5:10 pm

MikeGL wrote:
Sun Jun 21, 2020 2:54 pm
+M25


1 second for Crystal_20200526

Code: Select all

Crystal_20200526:
Found 511 tablebases
...
 15/43	00:00	 751 837	8 742 290	+5,88	1.Ng3+ Ke3 2.Nf1+ Ke4 3.Rxc5 bxc5 4.Rxh5 gxh5 5.Bf7 c4 6.Ng3+ Ke3 7.Nf5+ Ke4 8.Nd6+ Ke3 9.Nxc4+ Ke4 10.Nd6+ Ke3 11.Nf5+ Ke4 12.Ng3+ Ke3 13.Nf1+ Ke4 14.Be6 c5 15.Bf7 c4 16.Bxc4 Kf5 17.Ng3+ Kg6 18.Bxd3+ Kf7 19.Bxe2 fxe2+ 20.Kxe2 Ke6 21.Bd4 Kd7 22.Bxa7
 16/54	00:00	 874 485	8 658 267	+6,03	1.Ng3+ Ke3 2.Nf1+ Ke4 3.Rxc5 bxc5 4.Rxh5 gxh5 5.Bf7 c4 6.Ng3+ Ke3 7.Nf5+ Ke4 8.Nd6+ Ke3 9.Nxc4+ Ke4 10.Nd6+ Ke3 11.Nf5+ Ke4 12.Ng3+ Ke3 13.Nf1+ Ke4 14.Be6 c5 15.Bf7 c4 16.Bxc4 Kf5 17.Ng3+ Kg6 18.Bxd3+ Kf7 19.Bxe2 fxe2+ 20.Kxe2 f1Q+ 21.Nxf1 d1Q+ 22.Kxd1 Bf2 23.Kd2 Ke6
 17/56	00:00	 1 265 345	8 666 746	+6,12	1.Ng3+ Ke3 2.Nf1+ Ke4 3.Rxc5 bxc5 4.Rxh5 gxh5 5.Bf7 c4 6.Ng3+ Ke3 7.Nf5+ Ke4 8.Nd6+ Ke3 9.Nxc4+ Ke4 10.Nd6+ Ke3 11.Nf5+ Ke4 12.Ng3+ Ke3 13.Nf1+ Ke4 14.Be6 c5 15.Bf7 c4 16.Bxc4 Kf5 17.Ng3+ Kg6 18.Bxd3+ Kf7 19.Bxe2 fxe2+ 20.Kxe2 f1R 21.Nxf1 Kg6 22.Bd4 Bxh4 23.Bxa7 Be7 24.Nxd2
 18/55	00:00	 1 667 945	8 687 213	+6,93	1.Ng3+ Ke3 2.Nf1+ Ke4 3.Rxc5 bxc5 4.Rxh5 gxh5 5.Bf7 c4 6.Ng3+ Ke3 7.Nf5+ Ke4 8.Nd6+ Ke3 9.Nxc4+ Ke4 10.Nd6+ Ke3 11.Nf5+ Ke4 12.Ng3+ Ke3 13.Nf1+ Ke4 14.Be6 c5 15.Bf7 c4 16.Bxc4 Kf5 17.Ng3+ Kg6 18.Bxd3+ Kf7 19.Bxe2 fxe2+ 20.Kxe2 f1Q+ 21.Nxf1 d1R 22.Kxd1 Bf2 23.Ke2 Bc5 24.Ne3 Ke6 25.Kd3 Bd6 26.Bxd6 Kxd6 27.Ke4 Ke6 28.Nc4
 19/57	00:00	 3 337 041	9 092 754	+7,28	1.Ng3+ Ke3 2.Nf1+ Ke4 3.Rxc5 bxc5 4.Rxh5 gxh5 5.Bf7 c4 6.Ng3+ Ke3 7.Nf5+ Ke4 8.Nd6+ Ke3 9.Nxc4+ Ke4 10.Nd6+ Ke3 11.Nf5+ Ke4 12.Ng3+ Ke3 13.Nf1+ Ke4 14.Be6 c5 15.Bf7 c4 16.Bxc4 Kf5 17.Ng3+ Kg6 18.Bxd3+ Kf7 19.Bxe2 f1Q 20.Nxf1 fxe2+ 21.Kxe2 d1R 22.Kxd1 Bf2 23.Ke2 Bc5 24.Ne3 Ke6
 20/49	00:00	 5 652 016	8 872 866	+M25	1.Ng3+ Ke3 2.Nf1+ Ke4 3.Rxc5 bxc5 4.Rxh5 gxh5 5.Bf7 c4 6.Ng3+ Ke3 7.Nf5+ Ke4 8.Nd6+ Ke3 9.Nxc4+ Ke4 10.Nd6+ Ke3 11.Nf5+ Ke4 12.Ng3+ Ke3 13.Nf1+ Ke4 14.Be6 c5 15.Bf7 c4 16.Ng3+ Ke3 17.Nf5+ Ke4 18.Nd6+ Ke3 19.Nxc4+ Ke4 20.Nd6+ Ke3 21.Nf5+ Ke4 22.Ng3+ Ke3 23.Nf1+ Ke4 24.Be6 Re3 25.Ng3+
 21/49	00:00	 6 961 548	8 778 749	+M25	1.Ng3+ Ke3 2.Nf1+ Ke4 3.Rxc5 bxc5 4.Rxh5 gxh5 5.Bf7 c4 6.Ng3+ Ke3 7.Nf5+ Ke4 8.Nd6+ Ke3 9.Nxc4+ Ke4 10.Nd6+ Ke3 11.Nf5+ Ke4 12.Ng3+ Ke3 13.Nf1+ Ke4 14.Be6 c5 15.Bf7 c4 16.Ng3+ Ke3 17.Nf5+ Ke4 18.Nd6+ Ke3 19.Nxc4+ Ke4 20.Nd6+ Ke3 21.Nf5+ Ke4 22.Ng3+ Ke3 23.Nf1+ Ke4 24.Be6 Re3 25.Ng3+
 22/49	00:01	 9 251 881	8 811 315	+M25	1.Ng3+ Ke3 2.Nf1+ Ke4 3.Rxc5 bxc5 4.Rxh5 gxh5 5.Bf7 c4 6.Ng3+ Ke3 7.Nf5+ Ke4 8.Nd6+ Ke3 9.Nxc4+ Ke4 10.Nd6+ Ke3 11.Nf5+ Ke4 12.Ng3+ Ke3 13.Nf1+ Ke4 14.Be6 c5 15.Bf7 c4 16.Ng3+ Ke3 17.Nf5+ Ke4 18.Nd6+ Ke3 19.Nxc4+ Ke4 20.Nd6+ Ke3 21.Nf5+ Ke4 22.Ng3+ Ke3 23.Nf1+ Ke4 24.Be6 Re3 25.Ng3+

Dann Corbit
Posts: 11510
Joined: Wed Mar 08, 2006 7:57 pm
Location: Redmond, WA USA
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Re: Hard Puzzles found on Gameknot

Post by Dann Corbit » Sun Jun 21, 2020 7:28 pm

I have been remiss in reporting my results.
This is the one that I have not solved yet:
acd 49; bm Bxd6; ce 2043; dm 24; pv Bxd6;
These two I am verifying by 80 ply back-to-front searches of the pvs reported by Mike:

Code: Select all

8/1ppr4/br6/1pkp4/2p1Qp2/KPp2p2/B1PP1P2/8 w - - acd 125; bm d4+; ce 0; dm 62; pv d4+ Kd6 Qe5+ Kc6 Qe6+ Rd6 Qe8+ Rd7 Kb4 Kd6 Qe5+ Kc6 Qe6+ Rd6 Qe8+ Rd7 Bb1 Kd6 Qe5+ Kc6 Qe6+ Rd6 Qe8+ Rd7 Qe6+; 
4Q1R1/1pRp1rbp/1Pn2k1q/2P2prb/5Pp1/3p1pP1/3P1P1K/6B1 w - - acd 127; bm Rxc6+; ce 0; dm 63; pv Rxc6+ dxc6 Qe5+ Kg6 Qe6+ Rf6 Qe8+ Rf7 Kh1 Kf6 Qe5+ Kg6 Qe6+ Rf6 Qe8+ Rf7 Bh2 Kf6 Qe5+ Kg6 Qd6+ Rf6 Qe7 Rf8 Qe6+ Rf6 Qe8+ Rf7 Bg1; 
Here is the full set:
https://drive.google.com/file/d/1L_ApzW ... sp=sharing

I am also collecting all of the positions from :
jornalheiros.blogspot.com
Taking ideas is not a vice, it is a virtue. We have another word for this. It is called learning.
But sharing ideas is an even greater virtue. We have another word for this. It is called teaching.

MOBMAT
Posts: 315
Joined: Sat Feb 04, 2017 10:57 pm
Location: USA

Re: Hard Puzzles found on Gameknot (cooked?)

Post by MOBMAT » Sun Jun 21, 2020 9:00 pm

Um, this is a weird one. I was using Crystal 2.0 on this...

which the list had as a mate in 17. C2.0 found the mate after a couple of minutes, but I was away from the computer and didn't check back for a couple of hours. Here is what it reported (output from Arena)...

Code: Select all

Crystal 2.0:
 8	00:00	 19k	6,470k	-2.82	1.Qd3 c6 2.Qg3 Rxd5 3.Qxh2 Rf5+ 4.Kxg7 Rf1 5.Kh6 Nc3 6.Qxh3 Rxg1
 9	00:00	 27k	6,762k	-1.92	1.Qd3 c6 2.Qg3 Rxd5 3.Qxh2 Rf5+ 4.Kxg7 Rf1 5.Kh8 Nc3 6.g7 Rxg1 7.g8Q b1Q
 10	00:00	 51k	7,307k	-1.85	1.Qd3 c6 2.Qg3 Rxd5 3.Qxh2 Rf5+ 4.Kxg7 Rf1 5.Kh8 Nd2 6.Bf6 Rxg1 7.Qxg1+ Nf1 8.g7
 11	00:00	 119k	7,008k	 0.00	1.Qd3 c5 2.bxc5 Rd8+ 3.Bxd8
 12	00:00	 339k	6,529k	 0.00	1.Qd3 c5 2.bxc5 Rd8+ 3.Bxd8
 13	00:00	 736k	6,459k	 0.00	1.Qa3 c5 2.Qa4 Rxd5 3.Kxg7 cxb4 4.Bg3 Rc5 5.Bf4 Rc6 6.Be5 b3 7.Kh6 Re6 8.Bxh2 Rxg6+ 9.Kxg6
 14	00:00	 1,407k	6,310k	+2.38	1.Qa3 Rc6 2.Kxg7 Rc1 3.Rxc1 g1Q 4.Rxg1 Bxd5 5.Bf6 Be6 6.Qc3 Rg2 7.Rf1 Rf2 8.Re1
 15	00:00	 1,786k	6,137k	+5.51	1.Qa3 Rc6 2.Kxg7 Rc1 3.Rxc1 g1Q 4.Rxg1 Bxd5 5.Bf6 Be6 6.Re1 c6 7.b5 Rg2 8.Bxb2+ Rxb2 9.bxc6 Rc2 10.Qd6
 16	00:00	 2,326k	6,218k	+6.06	1.Qa3 c5 2.b5 Rxd5 3.Kxg7 Rd1 4.Rxd1 g1Q 5.Rxg1 Bd5 6.Bf6 c4 7.Re1 Re2 8.Bxb2+ Rxb2 9.Qxh3 Rc2 10.Qa3 Bb7 11.Kf7 Be4
 17	00:00	 3,462k	6,182k	+7.56	1.Qa3 c5 2.b5 Rxd5 3.Kxg7 Rd1 4.Rxd1 g1Q 5.Rxg1 Bb7 6.Bf6 c4 7.Kh6 Rf2 8.Bxb2+ Rxb2 9.Qxh3 Rb3 10.Qh2 c3 11.Qe5 Kb2 12.g7 a1Q 13.g8Q Qa2 14.Qf7
 18	00:01	 11,561k	5,848k	+10.11	1.Qa3 c5 2.b5 Rxd5 3.Kxg7 c4 4.Bf6 c3 5.b6 Rd1 6.Rxd1 g1Q 7.Rxg1 Bb7 8.Qxc3 Rg2 9.Qb3 Rd2 10.Qxh3 Rc2 11.Qb3 Rf2 12.Bxb2+ Rxb2 13.Qd3 Bf3 14.Qxf3
 19	00:02	 12,456k	5,856k	+11.76	1.Qa3 c5 2.b5 Rxd5 3.Kxg7 c4 4.Bf6 c3 5.b6 Rd7+ 6.Kh6 Rd1 7.Rxd1 g1Q 8.Rxg1 Bd5 9.Bxc3 Rc2 10.Bxb2+ Rxb2 11.Qxh3 Rb3 12.Qh2 Rh3+ 13.Qxh3 Kb2 14.Qd7 a1Q 15.Qxd5 Ka3 16.Qd3+ Qc3
 20	00:02	 15,268k	5,920k	+13.80	1.Qa3 c5 2.b5 Rxd5 3.Kxg7 c4 4.Bf6 c3 5.b6 Rd7+ 6.Kh6 Rd1 7.Rxd1 g1Q 8.Rxg1 Bd5 9.Bxc3 Rc2 10.Bxb2+ Rxb2 11.Qxh3 Rb3 12.Qh2 Rh3+ 13.Qxh3 Kb2 14.Qd7 a1Q 15.Qxd5 Qa3 16.Rg2+ Kc1 17.Qc4+ Nc3 18.g7 Qd6+ 19.Kh7
 21	00:02	 17,536k	5,971k	+15.00	1.Qa3 c5 2.b5 Rxd5 3.Kxg7 c4 4.Bf6 c3 5.b6 Rd7+ 6.Kh6 Rd1 7.Rxd1 g1Q 8.Rxg1 Bd5 9.Bxc3 Rc2 10.Bxb2+ Rxb2 11.Qxh3 Rb3 12.Qh2 Rh3+ 13.Qxh3 Kb2 14.Qd7 a1Q 15.Qxd5 Qa3
 22	00:04	 26,466k	6,068k	+15.00	1.Qa3 c5 2.b5 Rxd5 3.Kxg7 c4 4.Bf6 c3 5.b6 Rd7+ 6.Kh6 Rd1 7.Rxd1 g1Q 8.Rxg1 Bd5 9.Bxc3 Rc2 10.Bxb2+ Rxb2 11.Qxh3 Rb3 12.Qh2 Rh3+ 13.Qxh3 Kb2 14.Qd7 a1Q 15.Qxd5 Qa3 16.Rg2+ Kc1 17.Qc4+ Nc3 18.g7 Qd6+ 19.Kh7
 23+	00:04	 28,728k	6,062k	+15.09	1.Qa3
 23+	00:04	 28,885k	6,066k	+15.19	1.Qa3
 23+	00:05	 30,660k	6,088k	+17.42	1.Qa3
 23	00:05	 35,852k	6,135k	+15.36	1.Qa3 c5 2.b5 Rxd5 3.Kxg7 c4 4.Bf6 c3 5.b6 Rd7+ 6.Kh6 Rd1 7.Rxd1 g1Q 8.Rxg1 Bd5 9.Bxc3 Rc2 10.Bxb2+ Rxb2 11.Qxh3 Rb3 12.Qh2 Rh3+ 13.Qxh3 Kb2 14.Qd7 a1Q 15.Qxd5 Qa3 16.Rg2+ Kc3 17.b7 Qc1+ 18.Kg7 Qf4 19.Qc5+ Kb3 20.Qb5+ Kc3 21.b8Q Qxb8 22.Qxb8
 24+	00:05	 36,681k	6,145k	+15.46	1.Qa3
 24+	00:06	 36,958k	6,148k	+15.56	1.Qa3
 24+	00:06	 40,953k	6,213k	+20.71	1.Qa3
 24	00:06	 42,817k	6,229k	+18.33	1.Qa3 c5 2.b5 Rxd5 3.Kxg7 c4 4.Bf6 c3 5.b6 Rd1 6.Rxd1 g1Q 7.Rxg1 Bb7 8.Qxc3 Rg2 9.Qe3 Rc2 10.Qxh3 Be4 11.Qg3 Bf3 12.Qd6 Bb7 13.Qd3 Rf2 14.Qd4 Re2 15.Kh6 Bd5
 25+	00:07	 45,251k	6,241k	+18.43	1.Qa3
 25+	00:07	 45,328k	6,241k	+18.53	1.Qa3
 25+	00:11	 77,815k	6,507k	+37.34	1.Qa3
 25	00:12	 79,585k	6,521k	+27.30	1.Qa3 c5 2.b5 Rxd5 3.Kxg7 c4 4.Bf6 c3 5.b6 Rd7+ 6.Kh6 Rd1 7.Rxd1 g1Q 8.Rxg1 Bd5 9.Bxc3 Rc2 10.Bxb2+ Rxb2 11.Qxh3 Rb3 12.Qh2 Rc3 13.g7 Bg8 14.b7 Rc6+ 15.Kg5 Rc5+ 16.Kf6 Rc6+ 17.Ke7 Re6+ 18.Kd7 Re4 19.b8Q Rd4+ 20.Ke8 Bf7+ 21.Kxf7 Rf4+ 22.Qhxf4
 26+	00:12	 84,347k	6,542k	+27.40	1.Qa3
 26+	00:13	 85,098k	6,545k	+27.50	1.Qa3
 26+	00:13	 87,946k	6,543k	+60.52	1.Qa3
 26	00:16	 107,801k	6,559k	+65.58	1.Qa3 c5 2.b5 Rxd5 3.Kxg7 c4 4.Bf6 c3 5.b6 Rd7+ 6.Kh6 Rd1 7.Rxd1 g1Q 8.Rxg1 Bd5 9.Bxc3 Rc2 10.Bxb2+ Rxb2 11.Qxh3 Rc2 12.b7 Bxb7 13.Qb3 Rh2+ 14.Kg5 Rh3 15.Qb4 Rd3 16.Qxb7 Rd4 17.g7 Rb4 18.g8Q Rb5+ 19.Qgd5 Rxd5+ 20.Qxd5 Kb2 21.Rg2+ Kc3 22.Rxa2 Nd2 23.Qxd2+ Kc4 24.Qc1+ Kd5 25.Ra4 Ke6 26.Qc6+ Ke7
 27+	00:16	 109,997k	6,572k	+65.70	1.Qa3
 27+	00:16	 110,003k	6,572k	+66.02	1.Qa3
 27+	00:17	 112,693k	6,582k	+76.85	1.Qa3
 27	00:20	 134,605k	6,620k	+77.37	1.Qa3 c5 2.b5 Rxd5 3.Kxg7 c4 4.Bf6 c3 5.b6 Rd7+ 6.Kh6 Rd1 7.Rxd1 g1Q 8.Rxg1 Bd5 9.Bxc3 Rc2 10.Bxb2+ Rxb2 11.Qxh3 Rb3 12.Qh2 Rh3+ 13.Qxh3 Kb2 14.Qd7 a1Q 15.Qxd5 Qa4 16.Rg2+ Kc3 17.g7 Qf4+ 18.Kg6 Qb8 19.g8Q Qxg8+ 20.Qxg8 Kd4 21.b7 Na3 22.b8Q Nc2 23.Rxc2 Kd3
 28+	00:20	 138,612k	6,666k	+77.46	1.Qa3
 28+	00:20	 138,956k	6,670k	+77.69	1.Qa3
 28+	00:20	 139,231k	6,674k	+148.77	1.Qa3
 28-	00:22	 151,720k	6,731k	+76.82	1.Qa3 c5
 28+	00:22	 151,880k	6,731k	+148.88	1.Qa3
 28	00:32	 221,467k	6,901k	+M27	1.Qa3 c5 2.b5 Rxd5 3.Kxg7 c4 4.Bf6 c3 5.b6 Rd7+ 6.Kh6 Rd1 7.Rxd1 g1Q 8.Rxg1 Bd5 9.Bxc3 Rc2 10.Bxb2+ Rxb2 11.Qxh3 Rc2 12.b7 Bxb7 13.Qb3 Rh2+ 14.Kg5 Rh3 15.Qb4 Rd3 16.Qxb7 Rd4 17.g7 Rb4 18.g8Q Rb5+ 19.Qgd5 Rxd5+ 20.Qxd5 Kb2 21.Rg2+ Kc3 22.Rxa2 Nd2 23.Rxd2 Kb4 24.Rb2+ Kc3 25.Rb3+ Kc2 26.Qd3+ Kc1 27.Rb1+
 29	00:39	 278,450k	6,986k	+M27	1.Qa3 c5 2.b5 Rxd5 3.Kxg7 c4 4.Bf6 c3 5.b6 Rd7+ 6.Kh6 Rd1 7.Rxd1 g1Q 8.Rxg1 Bd5 9.Bxc3 Rc2 10.Bxb2+ Rxb2 11.Qxh3 Rc2 12.b7 Bxb7 13.Qb3 Rh2+ 14.Kg5 Rh3 15.Qb4 Rd3 16.Qxb7 Rd4 17.g7 Rb4 18.g8Q Rb5+ 19.Qgd5 Rxd5+ 20.Qxd5 Kb2 21.Rg2+ Kc3 22.Rxa2 Nd2 23.Rxd2 Kb4 24.Rb2+ Kc3 25.Rb3+ Kc2 26.Qd3+ Kc1 27.Rb1+
 30	00:58	 412,717k	7,094k	+M27	1.Qa3 c5 2.b5 Rxd5 3.Kxg7 c4 4.Bf6 c3 5.b6 Rd7+ 6.Kh6 Rd1 7.Rxd1 g1Q 8.Rxg1 Bd5 9.Bxc3 Rc2 10.Bxb2+ Rxb2 11.Qxh3 Rc2 12.b7 Bxb7 13.Qb3 Rh2+ 14.Kg5 Rh3 15.Qb4 Rd3 16.Qxb7 Rd4 17.g7 Rb4 18.g8Q Rb5+ 19.Qgd5 Rxd5+ 20.Qxd5 Kb2 21.Rg2+ Kc3 22.Rxa2 Nd2 23.Rxd2 Kb4 24.Rb2+ Kc3 25.Rb3+ Kc2 26.Qd3+ Kc1 27.Rb1+
 31	01:31	 655,575k	7,158k	+M26	1.Qa3 c5 2.b5 Rxd5 3.Kxg7 c4 4.Bf6 c3 5.b6 Rd7+ 6.Kh6 Rd1 7.Rxd1 g1Q 8.Rxg1 Bd5 9.Bxc3 Rc2 10.Bxb2+ Rxb2 11.Qxh3 Rc2 12.b7 Bxb7 13.Qb3 Rh2+ 14.Kg5 Rb2 15.Qc3 Ba6 16.Kh6 Bf1 17.Qd4 Nd2 18.g7 Kb1 19.Rxf1+ Kc2 20.g8Q Rb6+ 21.Qxb6 a1R 22.Rxa1 Kd3 23.Qgg6+ Ke2
 32	02:07	 912,825k	7,176k	+M17	1.Qa3 c5 2.Qa4 Rxd5 3.Bf6 cxb4 4.Qc2 gxf6 5.g7 Rd8+ 6.Kf7 Rd7+ 7.Kg6 Rd8 8.Kh7 Rd4 9.g8Q Rh4+ 10.Kg7 Rg4+ 11.Kf8 Rxg8+ 12.Kxg8 f5 13.Qb3 f4 14.Qxb4 f3 15.Qa4 f2 16.Rxb1+ Kxb1 17.Qd1+
 33	02:52	 1,239,128k	7,183k	+M17	1.Qa3 c5 2.Qa4 Rxd5 3.Bf6 cxb4 4.Qc2 gxf6 5.g7 Rd8+ 6.Kf7 Rd7+ 7.Kg6 Rd8 8.Kh7 Rd4 9.g8Q Rh4+ 10.Kg7 Rg4+ 11.Kf8 Rxg8+ 12.Kxg8 f5 13.Qb3 f4 14.Qxb4 f3 15.Qa4 f2 16.Rxb1+ Kxb1 17.Qd1+
 34	03:50	 1,652,936k	7,169k	+M17	1.Qa3 c5 2.Qa4 Rxd5 3.Bf6 cxb4 4.Qc2 gxf6 5.g7 Rd8+ 6.Kf7 Rd7+ 7.Kg6 Rd8 8.Kh7 Rd4 9.g8Q Rh4+ 10.Kg7 Rg4+ 11.Kf8 Rxg8+ 12.Kxg8 f5 13.Qb3 f4 14.Qxb4 f3 15.Qa4 f2 16.Rxb1+ Kxb1 17.Qd1+
 35	05:57	 2,581,207k	7,219k	+M17	1.Qa3 Rc6 2.Kxg7 Rc1 3.Bf6 Nxa3 4.Rxc1+ Nb1 5.Rg1 c5 6.b5 c4 7.b6 c3 8.b7 c2 9.b8Q c1Q 10.Rxc1 g1Q 11.Rxg1 Rf2 12.Rxh1 Rc2 13.Rh2 Nd2 14.Kh6 Kb1 15.Rh1+ Nf1 16.Rxf1+ Rc1 17.Qxb2+
 36	07:54	 3,435,686k	7,244k	+M17	1.Qa3 Rc6 2.Kxg7 Rc1 3.Bf6 Nxa3 4.Rxc1+ Nb1 5.Rg1 c5 6.b5 c4 7.b6 c3 8.b7 c2 9.b8Q c1Q 10.Rxc1 g1Q 11.Rxg1 Rf2 12.Rxh1 Rc2 13.Rh2 Nd2 14.Kh6 Kb1 15.Rh1+ Nf1 16.Rxf1+ Rc1 17.Qxb2+
 37	12:00	 5,259,948k	7,298k	+M17	1.Qa3 Rc6 2.Kxg7 Rc1 3.Bf6 Nxa3 4.Rxc1+ Nb1 5.Rg1 c5 6.b5 c4 7.b6 c3 8.b7 c2 9.b8Q c1Q 10.Rxc1 g1Q 11.Rxg1 Rf2 12.Rxh1 Rc2 13.Rh2 Nd2 14.Kh6 Kb1 15.Rh1+ Nf1 16.Rxf1+ Rc1 17.Qxb2+
 38	16:20	 7,194,308k	7,341k	+M17	1.Qa3 Rc6 2.Kxg7 Rc1 3.Bf6 Nxa3 4.Rxc1+ Nb1 5.Rg1 c5 6.b5 c4 7.b6 c3 8.b7 c2 9.b8Q c1Q 10.Rxc1 g1Q 11.Rxg1 Rf2 12.Rxh1 Rc2 13.Rh2 Nd2 14.Kh6 Kb1 15.Rh1+ Nf1 16.Rxf1+ Rc1 17.Qxb2+
 39	42:34	 19,088,989k	7,472k	+M13	1.Qc4 Rc6 2.Qc5 Rxg6 3.Bf2 Rg4 4.Bd4 Rf4+ 5.Kg8 Re4 6.Qc3 Re2 7.Qd3 Re8+ 8.Kf7 c5 9.Kxe8 cxd4 10.Qb3 d3 11.Qa4 d2 12.Rxb1+ Kxb1 13.Qd1+
Could someone verify the M13. Not sure if it is a glitch or a TT issue since my 16Gb of hash maxed out.
I will also start it on another engine just to verify.
i7-6700K @ 4.00Ghz (using 6 threads), EGTBs on PCI SSD
Benchmark: Stockfish 11 64 bmi2 (nps): 2067669

Dann Corbit
Posts: 11510
Joined: Wed Mar 08, 2006 7:57 pm
Location: Redmond, WA USA
Contact:

Re: Hard Puzzles found on Gameknot

Post by Dann Corbit » Sun Jun 21, 2020 11:25 pm

If you look in the file that I posted, I had the same key move and distance (dm 13):
Qc4 Rc6 Qc5 Rxg6 Qc2 Rg4 Bf2 Rf4+ Ke7 Rxb4 Be1 Rb8 Qa4 Rb7 Bf2 c6+ Kd6 Rb3 Qxb3 c5 Bxc5 g5 Bd4 g4 Qxb2+

There are many positions where the mate found is shorter than the mate distance suggested.
But there are also some where the mate I found is longer than the suggested mate. I guess I just need to search longer for those.
Taking ideas is not a vice, it is a virtue. We have another word for this. It is called learning.
But sharing ideas is an even greater virtue. We have another word for this. It is called teaching.

Vinvin
Posts: 4752
Joined: Thu Mar 09, 2006 8:40 am
Full name: Vincent Lejeune

Re: Hard Puzzles found on Gameknot (cooked?)

Post by Vinvin » Sun Jun 21, 2020 11:36 pm

MOBMAT wrote:
Sun Jun 21, 2020 9:00 pm
Um, this is a weird one. I was using Crystal 2.0 on this...

which the list had as a mate in 17. C2.0 found the mate after a couple of minutes, but I was away from the computer and didn't check back for a couple of hours. Here is what it reported (output from Arena)...

Code: Select all

Crystal 2.0:
...
 38	16:20	 7,194,308k	7,341k	+M17	1.Qa3 Rc6 2.Kxg7 Rc1 3.Bf6 Nxa3 4.Rxc1+ Nb1 5.Rg1 c5 6.b5 c4 7.b6 c3 8.b7 c2 9.b8Q c1Q 10.Rxc1 g1Q 11.Rxg1 Rf2 12.Rxh1 Rc2 13.Rh2 Nd2 14.Kh6 Kb1 15.Rh1+ Nf1 16.Rxf1+ Rc1 17.Qxb2+
 39	42:34	 19,088,989k	7,472k	+M13	1.Qc4 Rc6 2.Qc5 Rxg6 3.Bf2 Rg4 4.Bd4 Rf4+ 5.Kg8 Re4 6.Qc3 Re2 7.Qd3 Re8+ 8.Kf7 c5 9.Kxe8 cxd4 10.Qb3 d3 11.Qa4 d2 12.Rxb1+ Kxb1 13.Qd1+
Could someone verify the M13. Not sure if it is a glitch or a TT issue since my 16Gb of hash maxed out.
I will also start it on another engine just to verify.
It seems ok to me. Not easy to check, a lot of complex variations to check with Crystal.
5 best moves after 1.Qc4 gives distance to mate but 3 moves are longer than mate 12.
I checked this 3 subvariations (Rc6, c5 and c6) and they are all shorter or equal to #12.

It's very interesting to see how this shortest mate is hard to solve.

Code: Select all

Crystal_20200526:

 27/16	01:17	 904 153 237	11 682 622	+M8	1. ... Rxg6 2.b5 Rd6 3.Ke7 g5 4.Bg3 Rh6 5.Be5 Rh7+ 6.Ke8 Rf7 7.Qd4 Rf8+ 8.Kxf8 g4 9.Qxb2+
 27/20	01:17	 904 153 237	11 682 622	+M10	1. ... Rd7 2.Bf6 gxf6 3.Qc6 Rd8+ 4.Ke7 Rd6 5.Qa8 f5 6.g7 Rg6 7.Qa4 Rxg7+ 8.Kf6 Rg6+ 9.Kxg6 c5 10.Rxb1+ Kxb1 11.Qd1+
 27/24	01:17	 904 153 237	11 682 622	+M12	1. ... Rb6 2.Qb3 Rd6 3.b5 c5 4.b6 c4 5.Qa4 Rxd5 6.b7 Rf5+ 7.Kxg7 Rf1 8.b8Q Rxg1 9.Bf6 c3 10.Qba7 Na3 11.Qxg1+ Nb1 12.Qb3 c2 13.Qxb2+
 27/26	01:17	 904 153 237	11 682 622	+M13	1. ... Rc6 2.Qc5 Rxg6 3.Qc2 Rg4 4.Bf2 Rf4+ 5.Ke7 Rxb4 6.Bc5 Rb5 7.Bd4 c5 8.Qa4 Rb7+ 9.Ke6 Rb6+ 10.d6 Rb3 11.Qxb3 cxd4 12.Qa4 d3 13.Rxb1+ Kxb1 14.Qd1+
 27/28	01:17	 904 153 237	11 682 622	+M14	1. ... c5 2.Ke7 Rb6 3.d6 cxb4 4.d7 b3 5.Be1 Rb7 6.Qc5 Na3 7.Qe5 Nb1 8.Ke8 Rb4 9.d8Q Rc4 10.Qdd4 Rc8+ 11.Kf7 Rc2 12.Kxg7 Rd2 13.Qxd2 Nc3 14.Qexc3 Kb1 15.Qcxb2+
 27/30	01:17	 904 153 237	11 682 622	+M16	1. ... c6 2.Kxg7 c5 3.Bg3 Rb6 4.Be5 Rxb4 5.Qc3 Rb7+ 6.Kh6 c4 7.g7 Rb6+ 8.Bf6 Rb3 9.Qd4 c3 10.g8Q c2 11.Qa4 Rc3 12.Bxc3 c1Q+ 13.Rxc1 g1Q 14.Qxg1 Be4 15.Rxb1+ Bxb1 16.Qxb1+ Kxb1

Code: Select all

After 1...Rc6 :
 21/21	00:08	 74 923 239	8 353 577	+M12	2.Qc5 Rxc5 3.bxc5 c6 4.Bf6 cxd5 5.c6 gxf6 6.g7 d4 7.c7 d3 8.c8Q d2 9.Qc2 d1Q 10.Qxd1 f5 11.g8Q f4 12.Qdb3
----------------------------------------------------------------------------------------------------------
After 1...c5 :
 19/23	00:04	 32 970 045	7 958 012	+M12	2.Ke7 Rb6 3.d6 cxb4 4.Bf6 b3 5.Qd4 Rb7+ 6.d7 gxf6 7.g7 Rb5 8.d8Q Rb7+ 9.Kf8 Rb5 10.Qd1 Rf5 11.Qxb1+ axb1Q 12.Qa8+ Ra5 13.Qxa5+
----------------------------------------------------------------------------------------------------------
Ater 1...c6
 25/23	00:05	 46 076 235	8 110 585	+M12	2.b5 c5 3.Qa4 Rxd5 4.Bf6 gxf6 5.g7 Rd8+ 6.Ke7 Rd4 7.Qc2 Rg4 8.g8Q Rxg8 9.Qa4 Rg7+ 10.Ke6 Rd7 11.Kxd7 f5 12.Rxb1+ Kxb1 13.Qd1+

Dann Corbit
Posts: 11510
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Location: Redmond, WA USA
Contact:

Re: Hard Puzzles found on Gameknot

Post by Dann Corbit » Mon Jun 22, 2020 2:35 am

Here are the Epd records from jornalheiros.blogspot.com:
https://drive.google.com/file/d/11aeLNB ... sp=sharing
Taking ideas is not a vice, it is a virtue. We have another word for this. It is called learning.
But sharing ideas is an even greater virtue. We have another word for this. It is called teaching.

Dann Corbit
Posts: 11510
Joined: Wed Mar 08, 2006 7:57 pm
Location: Redmond, WA USA
Contact:

Re: Hard Puzzles found on Gameknot

Post by Dann Corbit » Mon Jun 22, 2020 2:42 am

analyzed records from jornalheiros.blogspot.com:
https://drive.google.com/file/d/1Jw3Wj3 ... sp=sharing
Taking ideas is not a vice, it is a virtue. We have another word for this. It is called learning.
But sharing ideas is an even greater virtue. We have another word for this. It is called teaching.

Ignacio
Posts: 150
Joined: Wed Mar 08, 2006 7:15 pm

Re: Hard Puzzles found on Gameknot

Post by Ignacio » Mon Jun 22, 2020 10:31 am

Dann Corbit wrote:
Sun Jun 21, 2020 7:28 pm
I have been remiss in reporting my results.
This is the one that I have not solved yet:
acd 49; bm Bxd6; ce 2043; dm 24; pv Bxd6;
These two I am verifying by 80 ply back-to-front searches of the pvs reported by Mike:

Code: Select all

8/1ppr4/br6/1pkp4/2p1Qp2/KPp2p2/B1PP1P2/8 w - - acd 125; bm d4+; ce 0; dm 62; pv d4+ Kd6 Qe5+ Kc6 Qe6+ Rd6 Qe8+ Rd7 Kb4 Kd6 Qe5+ Kc6 Qe6+ Rd6 Qe8+ Rd7 Bb1 Kd6 Qe5+ Kc6 Qe6+ Rd6 Qe8+ Rd7 Qe6+; 
4Q1R1/1pRp1rbp/1Pn2k1q/2P2prb/5Pp1/3p1pP1/3P1P1K/6B1 w - - acd 127; bm Rxc6+; ce 0; dm 63; pv Rxc6+ dxc6 Qe5+ Kg6 Qe6+ Rf6 Qe8+ Rf7 Kh1 Kf6 Qe5+ Kg6 Qe6+ Rf6 Qe8+ Rf7 Bh2 Kf6 Qe5+ Kg6 Qd6+ Rf6 Qe7 Rf8 Qe6+ Rf6 Qe8+ Rf7 Bg1; 
Here is the full set:
https://drive.google.com/file/d/1L_ApzW ... sp=sharing

I am also collecting all of the positions from :
jornalheiros.blogspot.com
Hi Dann.
1.Rxh4+ gh4 2.Be2+ Kg5 3.Bxd6 cd6 4.Rxd5+ cd5 5.d4 etc.
Best.
Ignacio

Ignacio
Posts: 150
Joined: Wed Mar 08, 2006 7:15 pm

Re: Hard Puzzles found on Gameknot

Post by Ignacio » Mon Jun 22, 2020 11:12 am

Ignacio wrote:
Mon Jun 22, 2020 10:31 am
Dann Corbit wrote:
Sun Jun 21, 2020 7:28 pm
I have been remiss in reporting my results.
This is the one that I have not solved yet:
acd 49; bm Bxd6; ce 2043; dm 24; pv Bxd6;
These two I am verifying by 80 ply back-to-front searches of the pvs reported by Mike:

Code: Select all

8/1ppr4/br6/1pkp4/2p1Qp2/KPp2p2/B1PP1P2/8 w - - acd 125; bm d4+; ce 0; dm 62; pv d4+ Kd6 Qe5+ Kc6 Qe6+ Rd6 Qe8+ Rd7 Kb4 Kd6 Qe5+ Kc6 Qe6+ Rd6 Qe8+ Rd7 Bb1 Kd6 Qe5+ Kc6 Qe6+ Rd6 Qe8+ Rd7 Qe6+; 
4Q1R1/1pRp1rbp/1Pn2k1q/2P2prb/5Pp1/3p1pP1/3P1P1K/6B1 w - - acd 127; bm Rxc6+; ce 0; dm 63; pv Rxc6+ dxc6 Qe5+ Kg6 Qe6+ Rf6 Qe8+ Rf7 Kh1 Kf6 Qe5+ Kg6 Qe6+ Rf6 Qe8+ Rf7 Bh2 Kf6 Qe5+ Kg6 Qd6+ Rf6 Qe7 Rf8 Qe6+ Rf6 Qe8+ Rf7 Bg1; 
Here is the full set:
https://drive.google.com/file/d/1L_ApzW ... sp=sharing

I am also collecting all of the positions from :
jornalheiros.blogspot.com
Hi Dann.
1.Rxh4+ gh4 2.Be2+ Kg5 3.Bxd6 cd6 4.Rxd5+ cd5 5.d4 etc.
Best.
Ignacio
The first position is mate in 59.
FEN: 8/1ppr4/br6/1pkp4/2p1Qp2/KPp2p2/B1PP1P2/8 w - - 0 1

Chest 5.2:
FEN: 8/1ppr4/br6/1pkp4/2p1Qp2/KPp2p2/B1PP1P2/8 w - - (7+12)
Position-Analysis: C0/R0/K3/P8/X20 W:4/22
Search for 1. Special-Mate [C0/R0/K0/P2/X3] in 126 ... (Hash=2044MB)
59 00:00 0 0 +M59 d2-d4+
Search completed ... (Time=0.32s)
Mate in 59 found ! (1. Solution in 00:00)
59/59 00:00 420.071 1.316.836 +M59 d2-d4+ Rc5-d6 De4-e5+ Rd6-c6 De5-e6+ Td7-d6 De6-e8+ Td6-d7 b3-b4 Rc6-d6 De8-e5+ Rd6-c6 De5-e6+ Td7-d6 De6-e8+ Td6-d7 Aa2-b3 Rc6-d6 De8-e5+ Rd6-c6 De5-e6+ Td7-d6 De6-e8+ Td6-d7 Ra3-a2 Rc6-d6 De8-e5+ Rd6-c6 De5-e6+ Td7-d6 De6-e8+ Td6-d7 Ra2-b1 c4xb3 c2xb3 Rc6-d6 De8-e5+ Rd6-c6 De5-e6+ Td7-d6 De6-e8+ Td6-d7 Rb1-c2 Rc6-d6 De8-e5+ Rd6-c6 De5-e6+ Td7-d6 De6-e8+ Td6-d7 Rc2xc3 Rc6-d6 De8-e5+ Rd6-c6 De5-e6+ Td7-d6 De6-e8+ Td6-d7 Rc3-d2 Rc6-d6 De8-e5+ Rd6-c6 De5-e6+ Td7-d6 De6-e8+ Td6-d7 Rd2-e1 Rc6-d6 De8-e5+ Rd6-c6 De5-e6+ Td7-d6 De6-e8+ Td6-d7 Re1-f1 Rc6-d6 De8-e5+ Rd6-c6 De5-e6+ Td7-d6 De6-e8+ Td6-d7 Rf1-g1 Rc6-d6 De8-e5+ Rd6-c6 De5-e6+ Td7-d6 De6-e8+ Td6-d7 Rg1-h2 Rc6-d6 De8-e5+ Rd6-c6 De5-e6+ Td7-d6 De6-e8+ Td6-d7 Rh2-h3 Rc6-d6 De8-e5+ Rd6-c6 De5-e6+ Td7-d6 De6-e8+ Td6-d7 Rh3-g4 Rc6-d6 De8-e5+ Rd6-c6 De5-e6+ Td7-d6 De6-e8+ Td6-d7 Rg4-f5 Rc6-d6 De8-e6+

The second position:
FEN: 4Q1R1/1pRp1rbp/1Pn2k1q/2P2prb/5Pp1/3p1pP1/3P1P1K/6B1 w - - 0 1

Chest 5.2:
FEN: 4Q1R1/1pRp1rbp/1Pn2k1q/2P2prb/5Pp1/3p1pP1/3P1P1K/6B1 w - - (11+14)
Position-Analysis: C0/R0/K2/P8/X18 W:5/23
Parameters found in Clipboard: #63; 06:19 @ C0/R0/K0/P2/X4;
Search for 1. Special-Mate [C0/R0/K2/P2/X4] in 63 ... (Hash=2044MB)
63 00:00 0 0 +M63 Tc7xc6+
Search completed ... (Time=0.23s)
Mate in 63 found ! (1. Solution in 00:00)
63/63 00:00 234.841 1.021.047 +M63 Tc7xc6+ d7xc6 De8-e5+ Rf6-g6 De5-e6+ Tf7-f6 De6-e8+ Tf6-f7 Rh2-h1 Rg6-f6 De8-e5+ Rf6-g6 De5-e6+ Tf7-f6 De6-e8+ Tf6-f7 Ag1-h2 Rg6-f6 De8-e5+ Rf6-g6 De5-e6+ Tf7-f6 De6-e8+ Tf6-f7 Rh1-g1 Rg6-f6 De8-e5+ Rf6-g6 De5-e6+ Tf7-f6 De6-e8+ Tf6-f7 Rg1-f1 Rg6-f6 De8-e5+ Rf6-g6 De5-e6+ Tf7-f6 De6-e8+ Tf6-f7 Rf1-e1 Rg6-f6 De8-e5+ Rf6-g6 De5-e6+ Tf7-f6 De6-e8+ Tf6-f7 Re1-d1 Rg6-f6 De8-e5+ Rf6-g6 De5-e6+ Tf7-f6 De6-e8+ Tf6-f7 Rd1-c1 Rg6-f6 De8-e5+ Rf6-g6 De5-e6+ Tf7-f6 De6-e8+ Tf6-f7 Rc1-b1 Rg6-f6 De8-e5+ Rf6-g6 De5-e6+ Tf7-f6 De6-e8+ Tf6-f7 Rb1-a2 Rg6-f6 De8-e5+ Rf6-g6 De5-e6+ Tf7-f6 De6-e8+ Tf6-f7 Ra2-b3 Rg6-f6 De8-e5+ Rf6-g6 De5-e6+ Tf7-f6 De6-e8+ Tf6-f7 Rb3-c4 Rg6-f6 De8-e5+ Rf6-g6 De5-e6+ Tf7-f6 De6-e8+ Tf6-f7 Rc4xd3 Rg6-f6 De8-e5+ Rf6-g6 De5-e6+ Tf7-f6 De6-e8+ Tf6-f7 Rd3-c4 Rg6-f6 De8-e5+ Rf6-g6 De5-e6+ Tf7-f6 De6-e8+ Tf6-f7 d2-d4 Rg6-f6 De8-e5+ Rf6-g6 De5-e6+ Tf7-f6 De6-e8+ Tf6-f7 d4-d5 c6xd5+ Rc4xd5 Rg6-f6 De8-e6+

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