Hard Puzzles found on Gameknot

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MikeGL
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Re: Hard Puzzles found on Gameknot

Post by MikeGL » Sat Jun 20, 2020 1:42 pm

+M27

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.

Dann Corbit
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Re: Hard Puzzles found on Gameknot

Post by Dann Corbit » Sat Jun 20, 2020 3:18 pm

https://drive.google.com/file/d/1L_ApzW ... sp=sharing
The 31 I did not yet solve are in the unsolved file.
The 1240 which are driven to mate are in the other file.
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But sharing ideas is an even greater virtue. We have another word for this. It is called teaching.

Dann Corbit
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Re: Hard Puzzles found on Gameknot

Post by Dann Corbit » Sat Jun 20, 2020 3:20 pm

MikeGL wrote:
Sat Jun 20, 2020 1:42 pm
+M27

Alterntively:
k4n2/ppp1NK1p/2pB2p1/1Q6/3p4/4rpb1/RP3rP1/4q1nb w - - acd 60; bm Rxa7+; ce 32714; dm 27; pv Rxa7+ Kxa7 Nxc6+ bxc6 Bc5+ Ka8 Qa6+ Kb8 Ba7+ Ka8 Bxd4+ Kb8 Ba7+ Ka8 Bxe3+ Kb8 Ba7+ Ka8 Bxf2+ Kb8 Ba7+ Ka8 Bxg1+ Kb8 Ba7+ Ka8 Be3+ Kb8 Qa7+ Kc8 Qa8+ Kd7 Qe8+ Kd6 Qxf8+ Kd5 Qc5+ Ke4 Qd4+ Kf5 Qd3+ Ke5 Bd4+ Kf4 Qxf3+ Kg5 Bf6+ Kh6 Qg4 Qe7+ Bxe7 Bxg2 Qg5+;
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
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Re: Hard Puzzles found on Gameknot

Post by Dann Corbit » Sat Jun 20, 2020 3:24 pm

MikeGL wrote:
Sat Jun 20, 2020 1:03 pm
Here's the possible Mate in 63 and also M62 solutions (using SF and manual analysis)
There's a glitch in M62 puzzle. My interface keeps on reporting 50-move-rule draw, because there's no capture.
Maybe that, or there is a more efficient mate reaching M62 with captures somewhere.



I found prior art for the second but not the first:
http://jornalheiros.blogspot.com/2020/0 ... novic.html
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MOBMAT
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Re: Hard Puzzles found on Gameknot

Post by MOBMAT » Sat Jun 20, 2020 3:58 pm

The 13s were pretty easy.


Crystal 2.0: +M13 1.Rxe6 fxe6 2.Kd8 Rh2 3.Kc7 Rh3 4.Kb6 Rh2 5.Bxb2 Rh3 6.Bd4 Rh2 7.Kc7 Rh3 8.Kd8 Rh2 9.Ke7 Rh3 10.f5 Rh2 11.f6 h3 12.Kd8 Nxc5 13.Nc3+


Crystal 2.0: +M13 1.Rxe6 dxe6 2.Kd8 Rh2 3.Kc7 Rh3 4.Kb6 Rh2 5.Bxb2 Rh3 6.Bd4 Rh2 7.Kc7 Rh3 8.Kd8 Rh2 9.Ke7 Rh3 10.f5 Rh2 11.f6 Rh3 12.Nxh3 Nxc5 13.Nc3+


Crystal 2.0: +M13 1.Qxg6+ Bxg6+ 2.Rxg6+ hxg6 3.Rd8 Kh7 4.Nxg5+ Kh6 5.Nf3 Kh7 6.Rd4 g5 7.Nxg5+ Kh6 8.Nf3 g5 9.Rd8 Kh7 10.Nxg5+ Kh6 11.Nf3 Kh7 12.Rd4 Rf1 13.Rh4+
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MOBMAT
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Re: Hard Puzzles found on Gameknot

Post by MOBMAT » Sat Jun 20, 2020 4:05 pm

14s were easy as well


Crystal 2.0: +M14 1.Rxc6+ bxc6 2.Bb3 Kb5 3.Rb7+ Ka6 4.Re7 Kb5 5.Ba4+ Ka6 6.Bd1 f3 7.Bb3 Kb5 8.Rb7+ Ka6 9.Rd7 Kb5 10.Ba4+ Ka6 11.Bc2 Rb8 12.Bd3+ Rb5 13.Bc5 h1Q 14.Ra7+


Crystal 2.0: +M14 1.Bxa6 bxa6 2.b7 a5 3.b8N a4 4.Nc6 dxc6 5.d7 c5 6.d8N c4 7.Ne6 fxe6 8.f7 e5 9.f5 e4 10.f8B e3 11.Bh6 e2 12.Re1 c1Q 13.Bxc1 Bxf5 14.B1xb2+


Crystal 2.0: +M14 1.Nf6+ Ke5 2.Bg6 hxg6 3.Ne8 Kd5 4.Nxc7+ Ke5 5.Ne8 Kd5 6.Nf6+ Ke5 7.Nd7+ Kd5 8.Nb6+ Ke5 9.Bc5 c2 10.Kf8 Nc3 11.Nd7+ Kd5 12.Nf6+ Ke5 13.d4+ Kxf6 14.Be7+


Crystal 2.0: +M14 1.Rxc6+ bxc6 2.Bb3 Kb5 3.Rb7+ Ka6 4.Re7 Kb5 5.Ba4+ Ka6 6.Bd1 f3 7.Bb3 Kb5 8.Rb7+ Ka6 9.Rd7 Kb5 10.Ba4+ Ka6 11.Bc2 Rb8 12.Bd3+ Rb5 13.Bc5 Kxa5 14.Ra7+
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MOBMAT
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Re: Hard Puzzles found on Gameknot

Post by MOBMAT » Sat Jun 20, 2020 5:10 pm

4 of 5 the M15


Crystal 2.0: +M15 1.Qxf6 gxf6 2.Rxd2 exd2 3.Bb3+ Kd3 4.Bd1 Kc4 5.Be2+ Kd5 6.Nb6+ Kc5 7.Nd7+ Kd5 8.Nxf6+ Kc5 9.Nd7+ Kd5 10.Nb6+ Kc5 11.Na4+ Kd5 12.Bd1 Kc4 13.Ke4 d5+ 14.Kf3 Bd6 15.Be2+


Crystal 2.0: +M15 1.Nb2+ Kb4 2.Bf4 Ka5 3.Ra3+ Kb4 4.Rg3 Ka5 5.Bc7+ Kb4 6.Bc2 a1N 7.Bf4 Ka5 8.Ra3+ Kb4 9.Rd3 Ka5 10.Bc7+ Kb4 11.Bd1 Bg2 12.Bb6 Nc2 13.Bxc2 Bd5 14.Bc5+ Ka5 15.Ra3+


Crystal 2.0: +M15 1.Rxa6 bxa6 2.Kb3 Kb1 3.Ng8 Ka1 4.Ne7 Kb1 5.Nc8 Ka1 6.Nb6 Kb1 7.Na8 Ka1 8.Nc7 Kb1 9.Nxa6 Ka1 10.Nc7 Kb1 11.Nb5 Ka1 12.Kc2 Ka2 13.Nc1+ Ka1 14.Nc3 e2 15.Nb3+


Crystal 2.0: +M15 1.Bxh6 gxh6 2.Rf4+ Kg5 3.Rg4+ Kf5 4.Nh4+ Kxe5 5.Ng6+ Kf5 6.Rf4+ Kg5 7.Rh4 Rh2 8.Rg4+ Kf5 9.Rd4 Nd6+ 10.cxd6 Rd2 11.Re4 Rd5 12.Ne7+ Kg5 13.Rg4+ Kh5 14.Nxd5 g2 15.Nf4+
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MOBMAT
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Re: Hard Puzzles found on Gameknot

Post by MOBMAT » Sat Jun 20, 2020 5:32 pm

The in 19s


Crystal 2.0: +M19 1.Rxe5+ Kxe5 2.Bd6+ Ke4 3.Re6+ Kf5 4.Re5+ Kf4 5.Re7+ Kf5 6.Be6+ Ke4 7.Bb3+ Kf5 8.Re5+ Kf4 9.Re6+ Kf5 10.Nc3 Rxc3 11.Re5+ Kf4 12.Re7+ Kf5 13.Be6+ Ke4 14.Bc4+ Kf5 15.Re5+ Kf4 16.Re6+ Kf5 17.e4+ dxe3 18.Rf6+ Ke4 19.Rf4+


Stockfish DEV 20061313: +M19 1.Qe2+ Kh1 2.Qf1+ Kh2 3.Bg1+ Kh1 4.Be3+ Kh2 5.Qe2+ Kh1 6.Qh5+ Kg2 7.Bh3+ Kh1 8.Be6+ Kg2 9.Qe2+ Kh1 10.Qf1+ Kh2 11.Bg1+ Kh1 12.Bd4+ Kh2 13.Qe2+ Kh1 14.Qxe4+ Kh2 15.Qe2+ Qg2 16.Qh5+ Kg3 17.Qg4+ Kh2 18.Qh4+ Qh3 19.Qxh3+
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Vinvin
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Re: Hard Puzzles found on Gameknot

Post by Vinvin » Sat Jun 20, 2020 6:37 pm

Nordlandia wrote:
Fri Jun 19, 2020 11:21 am
User Moremover on chess.com claims that many of the Puzzles are unsolved.

May be worth to examine further 😉

https://gameknot.com/chess-puzzles.pl?s ... de&m=0&s=9
Are they all "mate in x" problems ?

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Re: Hard Puzzles found on Gameknot

Post by MOBMAT » Sat Jun 20, 2020 6:57 pm

All the mate in 12 from Dan's list


Black-Diamond-XR7: +M12 1.Rh3+ Ng3 2.Ka5 Bh2 3.Kb6 Bg1 4.Kc7 Bh2 5.Kd8 Bg1 6.Ke7 Bh2 7.Kf8 Bg1 8.Kg7 Bh2 9.Kh6 Bg1 10.Kg5 Bh2 11.Kxh4 Bg1 12.Rxg3+


Black-Diamond-XR7: +M12 1.Rxh4 Nxh4 2.Kc2 Nf5 3.Nb3+ Kc4 4.Na5+ Kd4 5.Kb3 Ne7 6.g3 a6 7.Kc2 Nf5 8.Nb3+ Kc4 9.Nd2+ Kd4 10.Kb3 Nh4 11.gxh4 a5 12.Nf3+


Black-Diamond-XR7: +M12 1.Rxd6 exd6 2.Bd8 Bg5 3.Nf6 Be3 4.Ne8 Bg5 5.Ba5 Bxd2 6.Bd8 Bg5 7.Nf6 Be3 8.Nh5 Bg5 9.Bb6 Be3 10.Nd4 Bxd4 11.Bd8 b4 12.Bf6+


Black-Diamond-XR7: +M12 1.Nd3+ Kd5 2.c3 Nf3 3.Nf4+ Ke5 4.Nxg6+ Kd5 5.Nf4+ Ke5 6.Nd3+ Kd5 7.Bh7 e5 8.Bg8+ e6 9.Bh7 Nd2 10.Be4+ Nxe4 11.Rd4+ exd4 12.c4+


Black-Diamond-XR7: +M12 1.Nxb6+ axb6 2.Qh3 Qh2 3.Qf5 Qe2 4.Qh7 Qh2 5.Qh3 Qe2 6.Qg3 b2 7.Qh3 Qh2 8.Qf5 Qe2 9.Qh7 Qh2 10.Qh3 Bxd3 11.Qc8+ Qc7 12.Qxc7+


Black-Diamond-XR7: +M12 1.Nxb6+ cxb6 2.Qh3 Qh2 3.Qf5 Qe2 4.Qh7 Qh2 5.Qh3 Qe2 6.Qg3 b2 7.Qh3 Qh2 8.Qf5 Qe2 9.Qh7 Qh2 10.Qh3 Bxd3 11.Qc8+ Qc7 12.Qxc7+


Crystal 2.0: +M12 1.Nxg6+ fxg6 2.Qa3 Qa2 3.Qc5 Qd2 4.Qa7 Qa2 5.Qa3 Qd2 6.Qb3 g2 7.Qa3 Qa2 8.Qc5 Qd2 9.Qa7 Qa2 10.Qa3 Qd2 11.Qb3 Qf2 12.Nd5+
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