Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: test position. It's a mate in 11 alright :)

Author: Paul

Date: 04:48:14 10/07/01

Go up one level in this thread


On October 07, 2001 at 02:09:40, John Merlino wrote:

>On October 06, 2001 at 23:07:51, K. Burcham wrote:
>
>>
>>bruce posted a position similiar to this, i modified it for a mate in 11.
>>can your program see this mate in 11.
>>slate if you read this, will you post your analysis.
>>
>>
>> [D] 7b/q7/Pk3p1P/1Pp2pB1/K1P2P2/1Q6/8/8 w - - 0 1
>>
>>
>>kburcham
>
>CM8000 finds a Mate in 13 in a little less than an hour on my PIII-733:
>
>Time	Depth	Score	Positions	Moves
>0:00	1/4	4.21	2858		1. Qf3 Qc7 2. Bh4 Ka7 3. Qd5
>0:00	2/5	4.63	16232		1. Qf3 Qc7 2. Bh4 Qd7 3. Bf2 Qc8
>					4. Qb7+ Qxb7 5. axb7 Kxb7 6. Bxc5
>0:01	2/6	4.80	42505		1. Qf3 Qd7 2. Bh4 Ka7 3. Bf2 Kb6
>					4. Qa8 Qd1+ 5. Ka3 Qa1+ 6. Kb3
>0:02	3/7	4.63	101647		1. Qf3 Qd7 2. Bh4 Ka7 3. Bf2 Kb6
>					4. Qb7+ Qxb7 5. axb7 Kxb7 6. Bxc5
>0:02	3/7	5.61	143859		1. Qd3 Qe7 2. Bh4 Qc7 3. Qxf5 Qf7
>					4. Qd5 Qe7 5. Qa8
>0:04	4/8	6.27	397376		1. Qd3 Qe7 2. Bh4 Kc7 3. Qd5 Qe4
>					4. Qxc5+ Kd7 5. Qd5+ Ke7 6. Qxe4+
>					fxe4
>0:12	4/8	9.42	1168177		1. Qc3 Qd7 2. Bxf6 Ka7 3. Bxh8
>					Qd1+ 4. Ka3 Kb6 5. h7 Qe2 6. Be5
>0:16	5/9	9.46	1653617		1. Qc3 Qd7 2. Bxf6 Ka7 3. Bxh8
>					Qd1+ 4. Ka3 Kb6 5. h7 Qd6 6. Be5
>0:40	6/10	10.31	4509849		1. Qc3 Qd7 2. Bxf6 Ka7 3. Bxh8
>					Qd1+ 4. Ka3 Ka8 5. Be5 Qd7 6. Bd6
>					Ka7 7. Bxc5+ Kb8
>1:21	6/10	14.94	9642001		1. Qd3 Qc7 2. Bh4 Ka7 3. Bf2 Kb8
>					4. Bxc5 Qxc5 5. Qd8+ Qc8 6. a7+
>					Kb7 7. Qxc8+ Kxc8 8. a8=Q+ Kc7
>					9. Qxh8
>4:08	7/11	17.22	30748147	1. Qd3 Qe7 2. Bh4 Ka7 3. Qd5 Qc7
>					4. Bf2 Kb8 5. Qg8+ Qc8 6. a7+ Kb7
>					7. Qxc8+ Kxc8 8. a8=Q+ Kc7 9. Qxh8
>8:44	8/12	18.26	63137709	1. Qd3 Qe7 2. Bh4 Ka7 3. Qd5 Qc7
>					4. Bf2 Kb8 5. Qg8+ Qc8 6. a7+ Kb7
>					7. Qxc8+ Kxc8 8. a8=Q+ Kc7 9. Qxh8
>					Kd7 10. Qg7+ Ke6 11. Bxc5
>57:44	9/13	Mate13	432175230	1. Qd3 Qe7 2. Bh4 Kc7 3. a7 Qe8
>					4. Qd5 Qd7 5. Qxd7+ Kxd7 6. a8=Q
>					Kc7 7. Qc6+ Kd8 8. Bxf6+ Bxf6 9.
>					Qxf6+ Kc7 10. h7 Kb7 11. Qc6+ Ka7
>					12. Qc7+ Ka8 13. h8=Q#
>
>However, I have a suspicion that it's actually a Mate in 12. The improving move
>that the above is missing 4.Ka5. If I force 1.Qd3 Qe7 2.Bh4 Kc7 3.a7 Qe8, then I
>get:
>
>Time	Depth	Score	Positions	Moves
>0:00	2/5	15.50	14900		4. Qd5 Qe4 5. Qxe4 fxe4 6. a8=Q
>					e3 7. Qxh8
>0:00	2/6	16.31	52634		4. Qd5 Qe4 5. Qc6+ Qxc6 6. bxc6
>					Kxc6 7. a8=Q+ Kc7 8. Qxh8 Kd7 9.
>					Qxf6
>0:02	3/7	17.44	215703		4. Qd5 Qe4 5. Qxc5+ Kd8 6. Qd5+
>					Qxd5 7. cxd5 Kc7 8. a8=Q Kd6 9.
>					Qd8+ Kc5 10. Bf2+ Kc4 11. Qxh8
>					Kxd5 12. Qxf6
>0:05	3/7	24.76	629456		4. Ka5 Qe4 5. b6+ Kc8 6. Qd6 Qb7
>					7. Qf8+ Kd7 8. Qf7+ Kd6 9. Qxb7
>					Ke6 10. Qd5+ Ke7 11. Qxc5+ Ke6
>					12. Qd5+ Ke7 13. a8=Q
>0:07	4/8	Mate09	843073		4. Ka5 Qe4 5. b6+ Kc8 6. Qd6 Qb7
>					7. Qf8+ Kd7 8. Qf7+ Kd6 9. Qxb7
>					Ke6 10. a8=Q Kd6 11. Qc7+ Ke6 12.
>					Qac6#
>0:21	5/9	Mate09	2663784		4. Ka5 Qa8 5. b6+ Kc8 6. Qd6 Qb7
>					7. Qf8+ Kd7 8. Qf7+ Kd6 9. Qxb7
>					Ke6 10. a8=Q Kd6 11. Qc7+ Ke6 12.
>					Qac6#
>0:41	6/10	Mate09	5212517		4. Ka5 Qa8 5. b6+ Kc8 6. Qd6 Qb7
>					7. Qf8+ Kd7 8. Qf7+ Kd6 9. Qxb7
>					Ke6 10. a8=Q Kd6 11. Qc7+ Ke6 12.
>					Qd5#
>
>Notice that the mating move is White's 12th move. Is there something better in
>the first three moves that I'm missing?
>
>jm

Hi John,

Just ran the magnificent Chest of Heiner Marxen on this and it says it's a mate
in 11 alright:

Bh4 Qd7 Qf3 Ka7 Bf2 Kb6 Ka3 Qc8 Qd5 Kc7 Be1 Bg7 Ba5+ Kb8 hxg7 Ka7 Qf7+ Qc7 Qxc7+
Ka8 g8=Q#

There are 3 possible keymoves: Bh4, Qd3 or Qf3. I don't have the line for Qd3
unfortunately, my own program is still in deep thought on Qd3, stuck at a 19.92
score at the moment ... yep, Chest won this race! :)

Oh, and other programs probably have a hard time with this because check
extensions don't work very well here.

Groetjes,
Paul



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.