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Subject: Re: Mate in 12, how long .......

Author: Heiner Marxen

Date: 07:09:07 04/11/02

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On April 10, 2002 at 06:33:14, Kim Roper Jensen wrote:

>Hi
>
>Gentlemen start your engines....... :)
>
>[D]n7/4K3/3N4/3kN3/3P4/4B3/4pP1p/8 w - -
>
>Shredder 6 Paderborn on dual 1GHz with 256MB Hashtables
>
> 13.01	 0:00 	+11.26	1.Ne8 Ke4 (511.340) 760.9
> 14.01	 0:01 	+11.26	1.Ne8 Ke4 (929.237) 803.8
> 15.01	 0:02 	+11.26	1.Ne8 Ke4 (1.853.843) 835.4
> 16.01	 0:04 	+11.26	1.Ne8 Ke4 (3.612.247) 828.6
> 17.01	 0:07 	+11.26	1.Ne8 Ke4 2.Nd3 (6.457.467) 833.2
> 18.01	 0:13 	+11.26	1.Ne8 Ke4 2.f4 (11.662.860) 848.2
> 19.01	 0:24 	+11.26	1.Ne8 Ke4 2.Kd7 (20.703.699) 857.6
> 20.01	 1:30 	+11.51++	1.Ne8 Ke4 2.Nf6+ Kf5 3.Nh5 Ke4 4.Ng3+ Kd5 5.Nxe2 Ke4
>6.Ng3+ Kd5 7.f4 Nb6 8.f5 h1Q 9.Nxh1 Ke4 10.f6 Kxe3 11.f7 Nd7 12.Kxd7 Ke2 13.f8Q
>(76.896.816) 853.5
> 20.01	 1:32 	+12.01++	1.Ne8 Ke4 2.Nf6+ Kf5 3.Nh5 h1N 4.f3 Nf2 (78.445.711)
>851.5
> 20.01	 2:09 	  +M12	1.Ne8 Ke4 2.Nf6+ Kf5 3.Nh5 Ke4 4.Ng3+ Kd5 5.Nxe2 Ke4 6.Nc3+
>Kf5 7.Nb5 Ke4 8.Nd6+ Kd5 9.Nd3 Kc6 10.d5+ Kc7 11.Nb4 h1Q 12.Na6+ (111.023.499)
>854.5
> 21.01	 3:22 	  +M12	1.Ne8 Ke4 2.Nf6+ Kf5 3.Nh5 Ke4 4.Ng3+ Kd5 5.Nxe2 Ke4 6.Nc3+
>Kf5 7.Nb5 Ke4 8.Nd6+ Kd5 9.Nd3 Kc6 10.d5+ Kc7 11.Nb4 h1Q 12.Na6+ (175.664.572)
>868.6
> 22.01	 5:32 	  +M12	1.Ne8 Ke4 2.Nf6+ Kf5 3.Nh5 Ke4 4.Ng3+ Kd5 5.Nxe2 Ke4 6.Nc3+
>Kf5 7.Nb5 Ke4 8.Nd6+ Kd5 9.Nd3 Kc6 10.d5+ Kc7 11.Nb4 h1Q 12.Na6+ (295.046.375)
>887.3
>best move: Nd6-e8 time: 8:26.781 min  n/s: 897.849  CPU 194.3%  nodes:
>455.012.961 TB: 305.489

It takes much more time to confirm that this mate is unique and cannot be
shortened: on Athlon 1500+ with 128 MB hash and all 4-men and some 5-men
EGTBs Chest needs 9.2 hours.  Its PV:

PV: Ne8 Ke4 Nf6+ Kf5 Nh5 Ke4 Ng3+ Kd5 Nxe2 Ke4 Nc3+ Kf5 Nb5 Ke4 Nd6+ Kd5 Nd3 Kc6
d5+ Kc7 Nb4 h1=Q Na6#

Most of the time went into the last level:
#  4      0.03s [  3.00]        3kN [  7.58]  1.08        653-         0
#  5      0.20s [  6.67]       23kN [  7.46]  1.44       4856-         0
% EGTB found tables for max 5 pieces
% EGTB uses 3728.4K memory internally
#  6      1.21s [  6.05]      142kN [  6.07]  1.86      33771-         0
#  7      5.93s [  4.90]      794kN [  5.61]  2.29     197341-         0
#  8     29.91s [  5.04]     4042kN [  5.09]  2.75    1028620-       248
#  9    152.26s [  5.09]    19609kN [  4.85]  3.22    5068403-   1889442
# 10    875.69s [  5.75]   110543kN [  5.64]  3.26   29441110-  26241877
# 11   1794.12s [  2.05]   755709kN [  6.84]  3.38  200103574- 196904341
# 12  29241.12s [ 16.30]  4064342kN [  5.38]  3.57 1045223636-1042024403

To find "no mate in 11" was done in half an hour...
Somehow this timing looks fishy: over 6 fold the nodes done in only double
the time?  That 2.05 does not look ok... may be I have some problem
with my timing.  So, take that with a grain of salt.

Cheers,
Heiner



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