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Subject: Re: Position from yesterday, Rxc7!!, problem for all Rybka versions.

Author: Terry McCracken

Date: 20:35:08 02/09/06

Go up one level in this thread


On February 09, 2006 at 20:04:23, Robin Smith wrote:

>On February 09, 2006 at 19:03:23, Terry McCracken wrote:
>
>>On February 09, 2006 at 17:27:35, Uri Blass wrote:
>>
>>>On February 09, 2006 at 13:00:39, Andreas St. wrote:
>>>
>>>>Hi,
>>>>yesterday i posted this position:
>>>>
>>>>2r5/2pR1pk1/p1P3p1/P2K4/5P1p/5P1P/8/8 w - - 0 1
>>>>
>>>>and some users said, Rybka finds the solution.
>>>>
>>>>>Not Rybka 13b, but Rybka 1.0 Beta 32-bit (the first version!!!)
>>>>>Best regards,
>>>>>Orlando
>>>>
>>>>>Rybka 1.0 Beta 32-bit, sees Rxc7 quickly. I've no idea how the person testing
>>>>>whatever version had this failure.
>>>>
>>>>>Terry
>>>>
>>>>
>>>>What do you mean??? No Rybka version finds the only winning move Rxc7!
>>>
>>>
>>>Are you sure that it is the only winning move.
>>>Do you have a proof that f5 does not win?
>>
>>1. f5?! wins but isn't as good as the simple Rxc7!
>
>Hi Terry,
>
>I believe after 1.f5? that white has thrown away the win. For example:
>
>1.f5? g5! 2.Rxc7 Rxc7 3.Kd6 Rc8 4.Kd7 Ra8 5.c7 Kf6 6.c8Q Rxc8 7.Kxc8 Kxf5 8.Kb7
>Ke5 9.Kxa6 f5 =
>
Yes, I never really considered the consequences of f5?? as the move is
counterintuitive. White appears to have a draw at best.

Terry

>What line leads you to believe white can still win after 1.f5?
>
>-Robin
>
>>
>>Terry
>>>
>>>
>>>>If you analyse long enough, you will see, all Rybka versions prefers f5.
>>>>At the latest after one hour no Rxc7, but f5!
>>>>And look at the score of rybka. He sees nothing in this position.
>>>>Fritz 9 for example has +3.50 after 42sec.
>>>>Shredder 9 after 0 sec.! After 17sec. Score +3.05
>>>
>>>As Albert silver proved high score proves nothing here and Fritz9's score goes
>>>down later.
>>>
>>>Uri



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