Faster Forced Mate

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MikeGL
Posts: 1010
Joined: Thu Sep 01, 2011 2:49 pm

Faster Forced Mate

Post by MikeGL »

The published solution for the below position is Mate in 63 as per line 6429 of Chest.epd DB, but I attempted to solve it manually and there seems to be a mate in less than #30 moves.

[d]qrb5/bkPp3p/1p1B4/1p1KP3/1P2Pp2/R4P1p/P3pP1P/4N1n1 w - - 0 1

Is the solution of this Mate in 63 published somewhere or the label was wrong and the mate is actually around 30 moves?
Vinvin
Posts: 5228
Joined: Thu Mar 09, 2006 9:40 am
Full name: Vincent Lejeune

Re: Faster Forced Mate

Post by Vinvin »

What's the mainline ?
MikeGL
Posts: 1010
Joined: Thu Sep 01, 2011 2:49 pm

Re: Faster Forced Mate

Post by MikeGL »

Vinvin wrote:What's the mainline ?

Sorry, silly me.
Here's the possible solution but I can't find the tricky mate in 63 line.

[pgn][Event "Computer chess game"]
[Site "Talkchess"]
[Date "2017.06.26"]
[Round "?"]
[White "McBrain_2017"]
[Black "McBrain_2017"]
[Result "*"]
[BlackElo "2400"]
[TimeControl "0+2"]
[SetUp "1"]
[FEN "qrb5/bkPp3p/1p1B4/1p1KP3/1P2Pp2/R4P1p/P3pP1P/4N1n1 w - - 0 1"]
[Termination "unterminated"]
[PlyCount "24"]
[WhiteType "human"]
[BlackType "human"]
[Comment "bm #63;"]

1. Kd4 Kc6 2. Rc3+ Kb7 3. Kd3 Ka6 4. Ra3+ Kb7 5. Kd2 Kc6 6. Rc3+ Kb7 7. Nc2
Ka6 8. Ra3+ Kb7 9. Nd4 h6 10. Ke1 h5 11. Kd2 e1=Q+ 12. Kxe1 Ne2 *
[/pgn]

After the final position of these moves, mate can be found easily by most engines.
Vinvin
Posts: 5228
Joined: Thu Mar 09, 2006 9:40 am
Full name: Vincent Lejeune

Re: Faster Forced Mate

Post by Vinvin »

MikeGL wrote:
Vinvin wrote:What's the mainline ?

Sorry, silly me.
Here's the possible solution but I can't find the tricky mate in 63 line.

...

After the final position of these moves, mate can be found easily by most engines.
With backward analyse, McBrain announces mate in 18 in the starting position :-)

Code: Select all

FEN: qrb5/bkPp3p/1p1B4/1p1KP3/1P2Pp2/R4P1p/P3pP1P/4N1n1 w - - 0 1

McBrain_2017_v25_x64_modern:
...
 13/24	00:00	 19k	4 820k	+M18	1.Kd4 Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Nd4 h4 9.Ra3 e1R 10.Kxe1 Ne2 11.Nxe2 Kc6 12.Nd4+ Kb7
 14/26	00:00	 25k	6 157k	+M18	1.Kd4 Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Ra3 Nxf3+ 9.Rxf3 Ka6 10.Ra3+ Kb7 11.Ke1 Kc6 12.Nd4+ Kb7 13.Nf3
 15/29	00:00	 35k	7 076k	+M19	1.Kd4 Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Ra3 Nxf3+ 9.Rxf3 Ka6 10.Ra3+ Kb7 11.Ke1 Kc6 12.Nd4+ Kb7 13.Nf3 Kc6 14.Rc3+ Kb7 15.Ng5
 16/29	00:00	 38k	7 679k	+M18	1.Kd4 Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Ra3 Nxf3+ 9.Rxf3 Ka6 10.Ra3+ Kb7 11.Nd4 e1R 12.Kxe1 f3 13.Nxf3 h4 14.Ng5
 17/29	00:00	 41k	6 842k	+M18	1.Kd4 Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Ra3 Nxf3+ 9.Rxf3 Ka6 10.Ra3+ Kb7 11.Nd4 e1R 12.Kxe1 f3 13.Nxf3 h4 14.Ng5
 18/29	00:00	 44k	7 283k	+M18	1.Kd4 Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Ra3 Nxf3+ 9.Rxf3 Ka6 10.Ra3+ Kb7 11.Nd4 e1R 12.Kxe1 f3 13.Nxf3 h4 14.Ng5
 19/30	00:00	 47k	7 777k	+M18	1.Kd4 Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Ra3 Nxf3+ 9.Rxf3 Ka6 10.Ra3+ Kb7 11.Nd4 e1R 12.Kxe1 f3 13.Nxf3 h4 14.Ng5 Kc6 15.Rc3+ Kb7
 20/32	00:00	 50k	8 401k	+M18	1.Kd4 Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Ra3 Nxf3+ 9.Rxf3 Ka6 10.Ra3+ Kb7 11.Nd4 e1R 12.Kxe1 f3 13.Nxf3 h4 14.Ng5 Kc6 15.Rc3+ Kb7 16.Nf7 Ka6
 21/36	00:00	 55k	7 899k	+M18	1.Kd4 Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Ra3 Nxf3+ 9.Rxf3 Ka6 10.Ra3+ Kb7 11.Nd4 e1R 12.Kxe1 f3 13.Nxf3 h4 14.Ng5 Kc6 15.Rc3+ Kb7 16.Nf7 Ka6 17.Ra3+ Kb7 18.Nd8+
 22/36	00:00	 61k	8 666k	+M18	1.Kd4 Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Ra3 Nxf3+ 9.Rxf3 Ka6 10.Ra3+ Kb7 11.Nd4 e1R 12.Kxe1 f3 13.Nxf3 h4 14.Ng5 Kc6 15.Rc3+ Kb7 16.Nf7 Ka6 17.Ra3+ Kb7 18.Nd8+
 23/36	00:00	 67k	8 362k	+M18	1.Kd4 Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Ra3 Nxf3+ 9.Rxf3 Ka6  
MikeGL
Posts: 1010
Joined: Thu Sep 01, 2011 2:49 pm

Re: Faster Forced Mate

Post by MikeGL »

Vinvin wrote:
MikeGL wrote:
Vinvin wrote:What's the mainline ?

Sorry, silly me.
Here's the possible solution but I can't find the tricky mate in 63 line.

...

After the final position of these moves, mate can be found easily by most engines.
With backward analyse, McBrain announces mate in 18 in the starting position :-)
FEN: qrb5/bkPp3p/1p1B4/1p1KP3/1P2Pp2/R4P1p/P3pP1P/4N1n1 w - - 0 1

McBrain_2017_v25_x64_modern:
...
13/24 00:00 19k 4 820k +M18 1.Kd4 Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Nd4 h4 9.Ra3 e1R 10.Kxe1 Ne2 11.Nxe2 Kc6 12.Nd4+ Kb7
14/26 00:00 25k 6 157k +M18 1.Kd4 Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Ra3 Nxf3+ 9.Rxf3 Ka6 10.Ra3+ Kb7 11.Ke1 Kc6 12.Nd4+ Kb7 13.Nf3
15/29 00:00 35k 7 076k +M19 1.Kd4 Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Ra3 Nxf3+ 9.Rxf3 Ka6 10.Ra3+ Kb7 11.Ke1 Kc6 12.Nd4+ Kb7 13.Nf3 Kc6 14.Rc3+ Kb7 15.Ng5
16/29 00:00 38k 7 679k +M18 1.Kd4 Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Ra3 Nxf3+ 9.Rxf3 Ka6 10.Ra3+ Kb7 11.Nd4 e1R 12.Kxe1 f3 13.Nxf3 h4 14.Ng5
17/29 00:00 41k 6 842k +M18 1.Kd4 Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Ra3 Nxf3+ 9.Rxf3 Ka6 10.Ra3+ Kb7 11.Nd4 e1R 12.Kxe1 f3 13.Nxf3 h4 14.Ng5
18/29 00:00 44k 7 283k +M18 1.Kd4 Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Ra3 Nxf3+ 9.Rxf3 Ka6 10.Ra3+ Kb7 11.Nd4 e1R 12.Kxe1 f3 13.Nxf3 h4 14.Ng5
19/30 00:00 47k 7 777k +M18 1.Kd4 Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Ra3 Nxf3+ 9.Rxf3 Ka6 10.Ra3+ Kb7 11.Nd4 e1R 12.Kxe1 f3 13.Nxf3 h4 14.Ng5 Kc6 15.Rc3+ Kb7
20/32 00:00 50k 8 401k +M18 1.Kd4 Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Ra3 Nxf3+ 9.Rxf3 Ka6 10.Ra3+ Kb7 11.Nd4 e1R 12.Kxe1 f3 13.Nxf3 h4 14.Ng5 Kc6 15.Rc3+ Kb7 16.Nf7 Ka6
21/36 00:00 55k 7 899k +M18 1.Kd4 Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Ra3 Nxf3+ 9.Rxf3 Ka6 10.Ra3+ Kb7 11.Nd4 e1R 12.Kxe1 f3 13.Nxf3 h4 14.Ng5 Kc6 15.Rc3+ Kb7 16.Nf7 Ka6 17.Ra3+ Kb7 18.Nd8+
22/36 00:00 61k 8 666k +M18 1.Kd4 Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Ra3 Nxf3+ 9.Rxf3 Ka6 10.Ra3+ Kb7 11.Nd4 e1R 12.Kxe1 f3 13.Nxf3 h4 14.Ng5 Kc6 15.Rc3+ Kb7 16.Nf7 Ka6 17.Ra3+ Kb7 18.Nd8+
23/36 00:00 67k 8 362k +M18 1.Kd4 Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Ra3 Nxf3+ 9.Rxf3 Ka6

I think the highlighted move above 7...h5 makes the mate faster, because the trick is to delay everything and 7...h6 could be stronger and might hold the mate longer.
Last edited by MikeGL on Mon Jun 26, 2017 7:17 pm, edited 1 time in total.
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Nordlandia
Posts: 2821
Joined: Fri Sep 25, 2015 9:38 pm
Location: Sortland, Norway

Re: Faster Forced Mate

Post by Nordlandia »

Mike Libanan: that puzzle is resembles Otto Bláthy's compositions.
Vinvin
Posts: 5228
Joined: Thu Mar 09, 2006 9:40 am
Full name: Vincent Lejeune

Re: Faster Forced Mate

Post by Vinvin »

With SF, after 1.Kd4 :

Code: Select all

FEN: qrb5/bkPp3p/1p1B4/1p2P3/1P1KPp2/R4P1p/P3pP1P/4N1n1 b - - 1 1

Stockfish_170616_x64_modern:

 70/35	00:22	 326 616k	14 458k	+M15	1. ... h5 2.Kd3 h4 3.Kd2 Kc6 4.Rc3+ Kb7 5.Nc2 e1R 6.Kxe1 Ne2 7.Kxe2 Ka6 8.Ra3+ Kb7 9.Ke1 Kc6 10.Nd4+ Kb7 11.Nf5 Kc6 12.Rc3+ Kb7 13.Bf8 Ka6 14.Nd6 Qxe4+ 15.fxe4 f3 16.Ra3+
 71/35	00:22	 326 616k	14 458k	+M15	1. ... h6 2.Kd3 Kc6 3.Rc3+ Kb7 4.Kd2 h5 5.Nc2 Ka6 6.Ra3+ Kb7 7.Nd4 e1R 8.Kxe1 h4 9.Nf5 Nxf3+ 10.Rxf3 Ka6 11.Ra3+ Kb7 12.Nh6 Kc6 13.Rc3+ Kb7 14.Nf7 f3 15.Nd8+ Ka6 16.Ra3+
 71/35	00:22	 326 616k	14 458k	+M17	1. ... Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Nd4 Ka6 9.Ra3+ Kb7 10.Ke1 h4 11.Nf5 Kc6 12.Rc3+ Kb7 13.Nh6 Ka6 14.Nf7 Nxf3+ 15.Rxf3 Qxe4 16.Ra3+ Kb7 17.Nd8+ Ka8 18.cxb8Q+

MikeGL
Posts: 1010
Joined: Thu Sep 01, 2011 2:49 pm

Re: Faster Forced Mate

Post by MikeGL »

Vinvin wrote:With SF, after 1.Kd4 :

Code: Select all

FEN: qrb5/bkPp3p/1p1B4/1p2P3/1P1KPp2/R4P1p/P3pP1P/4N1n1 b - - 1 1

Stockfish_170616_x64_modern:

 70/35	00:22	 326 616k	14 458k	+M15	1. ... h5 2.Kd3 h4 3.Kd2 Kc6 4.Rc3+ Kb7 5.Nc2 e1R 6.Kxe1 Ne2 7.Kxe2 Ka6 8.Ra3+ Kb7 9.Ke1 Kc6 10.Nd4+ Kb7 11.Nf5 Kc6 12.Rc3+ Kb7 13.Bf8 Ka6 14.Nd6 Qxe4+ 15.fxe4 f3 16.Ra3+
 71/35	00:22	 326 616k	14 458k	+M15	1. ... h6 2.Kd3 Kc6 3.Rc3+ Kb7 4.Kd2 h5 5.Nc2 Ka6 6.Ra3+ Kb7 7.Nd4 e1R 8.Kxe1 h4 9.Nf5 Nxf3+ 10.Rxf3 Ka6 11.Ra3+ Kb7 12.Nh6 Kc6 13.Rc3+ Kb7 14.Nf7 f3 15.Nd8+ Ka6 16.Ra3+
 71/35	00:22	 326 616k	14 458k	+M17	1. ... Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Nd4 Ka6 9.Ra3+ Kb7 10.Ke1 h4 11.Nf5 Kc6 12.Rc3+ Kb7 13.Nh6 Ka6 14.Nf7 Nxf3+ 15.Rxf3 Qxe4 16.Ra3+ Kb7 17.Nd8+ Ka8 18.cxb8Q+

Thanks Jon and thanks Vincent maybe the #63 label was just a typo then.
Will post that Mate in 82 shortly, which seems to have a shorter solution too.
MikeGL
Posts: 1010
Joined: Thu Sep 01, 2011 2:49 pm

Re: Faster Forced Mate #82

Post by MikeGL »

[d]8/1p1p2p1/5p1p/5P1P/1p1p1P2/pP1P1P2/P1k1B3/4K3 w - - 0 1

The published solution for this is Mate in #82 at line 6466 of Chest.EPD file. But when I attempted to solve this manually, the solution seems to be around 40 moves.

[pgn]
[Event "Computer chess game"]
[Site "Talkchess"]
[Date "2017.06.27"]
[Round "?"]
[White "McBrain_2017"]
[Black "SF8_17061704"]
[Result "1-0"]
[BlackElo "2400"]
[Time "00:48:07"]
[TimeControl "0+2"]
[SetUp "1"]
[FEN "8/1p1p2p1/5p1p/5P1P/1p1p1P2/pP1P1P2/P1k1B3/4K3 w - - 0 1"]
[Termination "normal"]
[PlyCount "79"]
[WhiteType "human"]
[BlackType "human"]
[Comment "bm #82;"]

1. Bf1 Kc1 2. Bh3 Kc2 3. Ke2 Kc1 4. Bg2 Kc2 5. Bf1 Kc1 6. Ke1 Kc2 7. Be2
Kc1 8. Bd1 Kb2 9. Kd2 Kb1 10. Be2 Kb2 11. Bf1 Kb1 12. Bh3 Kb2 13. Bg2 Kb1
14. Bf1 Kb2 15. Be2 Kb1 16. Bd1 Kb2 17. Bc2 Ka1 18. Kc1 Kxa2 19. Bd1 Ka1
20. Be2 Ka2 21. Kc2 Ka1 22. Bf1 Ka2 23. Bh3 Ka1 24. Bg2 Ka2 25. Bf1 Ka1 26.
Be2 Ka2 27. Bd1 Ka1 28. Kc1 Ka2 29. Bc2 Ka1 30. Bb1 a2 31. Bc2 b6 32. Bd1
d6 33. Kc2 d5 34. Kc1 b5 35. Bc2 g6 36. hxg6 h5 37. g7 h4 38. g8=Q h3 39.
Qxd5 h2 40. Qxd4# 1-0
[/pgn]
Vinvin
Posts: 5228
Joined: Thu Mar 09, 2006 9:40 am
Full name: Vincent Lejeune

Re: Faster Forced Mate

Post by Vinvin »

MikeGL wrote:
Vinvin wrote:With SF, after 1.Kd4 :

Code: Select all

FEN: qrb5/bkPp3p/1p1B4/1p2P3/1P1KPp2/R4P1p/P3pP1P/4N1n1 b - - 1 1

Stockfish_170616_x64_modern:

 70/35	00:22	 326 616k	14 458k	+M15	1. ... h5 2.Kd3 h4 3.Kd2 Kc6 4.Rc3+ Kb7 5.Nc2 e1R 6.Kxe1 Ne2 7.Kxe2 Ka6 8.Ra3+ Kb7 9.Ke1 Kc6 10.Nd4+ Kb7 11.Nf5 Kc6 12.Rc3+ Kb7 13.Bf8 Ka6 14.Nd6 Qxe4+ 15.fxe4 f3 16.Ra3+
 71/35	00:22	 326 616k	14 458k	+M15	1. ... h6 2.Kd3 Kc6 3.Rc3+ Kb7 4.Kd2 h5 5.Nc2 Ka6 6.Ra3+ Kb7 7.Nd4 e1R 8.Kxe1 h4 9.Nf5 Nxf3+ 10.Rxf3 Ka6 11.Ra3+ Kb7 12.Nh6 Kc6 13.Rc3+ Kb7 14.Nf7 f3 15.Nd8+ Ka6 16.Ra3+
 71/35	00:22	 326 616k	14 458k	+M17	1. ... Kc6 2.Rc3+ Kb7 3.Kd3 Ka6 4.Ra3+ Kb7 5.Kd2 Kc6 6.Rc3+ Kb7 7.Nc2 h5 8.Nd4 Ka6 9.Ra3+ Kb7 10.Ke1 h4 11.Nf5 Kc6 12.Rc3+ Kb7 13.Nh6 Ka6 14.Nf7 Nxf3+ 15.Rxf3 Qxe4 16.Ra3+ Kb7 17.Nd8+ Ka8 18.cxb8Q+

Thanks Jon and thanks Vincent maybe the #63 label was just a typo then.
Will post that Mate in 82 shortly, which seems to have a shorter solution too.
Chest.EPD is very old thing ;-)