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Subject: Response to Mr. Walker.

Author: Timothy J. Frohlick

Date: 09:39:31 02/02/01

On February 02, 2001 at 12:10:58, James T. Walker wrote:

>On February 02, 2001 at 03:19:14, Timothy J. Frohlick wrote:
>
>>On February 02, 2001 at 01:28:59, Jouni Uski wrote:
>>
>>>[D]8/6kn/3B3p/5K1B/8/8/8/8 b - -
>>>
>>>resign 1-0! Why? Is this really white's win?
>>>
>>>JouniDate: 1/2/2001
>>
>>Jouni,
>>
>>Gambit Tiger without tablebases solves this as a mate in 46 in 26 minutes on a
>>PII 333 with 48 Megs Hash.
>>
>>1... Ng5 2. Bc5 Nf7 3. Bd4+ Kf8 4. Kf6 Ng5 5. Bc5+ Kg8 6. Kf5 Nf7 7. Be7 Ng5 8.
>>Bb4 Nf7 9. Kg6 Ne5+ 10. Kf6 Nd7+ 11. Ke7 Ne5 12. Bc3 Nc6+ 13. Ke8 Kh7 14. Kf7
>>Ne5+ 15. Kf6 Nc6 16. Bf3 Nd8 17. Bb4 h5 18. Be4+ Kh8 19. Be7 Nc6 20. Bxc6 Kh7
>>21. Be4+ Kg8 22. Kg6 Kh8 23. Bd5 h4 24. Bf6#
>>
>>
>>1-0
>>
>>Maybe tablebases are not all that great after all.  They don't always find the
>>shortest solution to a problem.
>>
>>Tim Frohlick
>
>Why mate in 46 and then you give a mate in 24 line?  I believe the "mate in 46"
>is true as Shredder 5 finds a mate in 47 (maybe a difference in terms) but where
>did the above line which is 24 moves come from?
>Jim

Jim,

Mate in 46 ply or 23 moves that is.  I do believe that this is the shortest
mate.  It sounds better to say the bigger number even though that is not how you
claim "mate in".  What I did to solve the above problem was to let GT run out to
14 or 15 ply seaarches and hand-pick the end move.  It seems that the "horizon
effect" can be partially eliminated by this method.  In addition, I think that
GT would not even get to a 46 ply search in a week of searching on a 333 Pentium
II.  The intelligent way to solve these long mate problems without a tablebase
is to do what I have done.

It is not "Green" ie environmentally friendly to let one's computer run for days
just to solve one chess problem..  N'est pas?

Tim "Save the Electrons" Frohlick

Re: Response to Mr. Walker. James T. Walker 10:28:18 02/02/01
- Re: Response to Mr. Walker. Robert Hyatt 14:56:52 02/02/01
- Re: Response to Mr. Walker. Paul 10:46:34 02/02/01
  - Re: Response to Mr. Walker. Dieter Buerssner 17:45:01 02/02/01
    - Re: Egtb mates and Paul 18:10:54 02/02/01
      - Re: Egtb mates and Dieter Buerssner 05:27:24 02/04/01
        
        Re: Egtb mates and upper bounds Paul 06:46:59 02/05/01
        
        Re: Egtb mates and upper bounds Hermano Ecuadoriano 07:57:14 02/05/01
        
        Re: Egtb mates and upper bounds Hermano Ecuadoriano 08:28:28 02/05/01
        
        Re: Egtb mates and upper bounds Paul 08:32:55 02/05/01
        
        Re: Egtb mates and upper bounds Paul 08:10:02 02/05/01
        
        Re: Egtb mates and Hermano Ecuadoriano 08:48:44 02/04/01
        
        Re: Egtb mates and Paul 11:06:15 02/04/01
        
        Re: Egtb mates and Paul 06:07:30 02/04/01
      - Re: Egtb mates and Robert Hyatt 21:44:37 02/03/01
- Re: Response to Mr. Walker. James T. Walker 10:31:38 02/02/01

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