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Subject: Re: Christmas Tree Problem

Author: Sune Larsson

Date: 00:48:30 12/25/05

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On December 25, 2005 at 03:22:56, Uri Blass wrote:

>On December 25, 2005 at 03:03:00, Sune Larsson wrote:
>
>>On December 25, 2005 at 02:43:23, John Merlino wrote:
>>
>>>On December 25, 2005 at 02:32:15, Uri Blass wrote:
>>>
>>>>On December 25, 2005 at 02:24:19, Sune Larsson wrote:
>>>>
>>>>>On December 24, 2005 at 20:49:48, John Merlino wrote:
>>>>>
>>>>>>On December 24, 2005 at 20:30:05, Alessandro Scotti wrote:
>>>>>>
>>>>>>>On December 24, 2005 at 20:14:19, Mark Ryan wrote:
>>>>>>>
>>>>>>>>http://www2.forthnet.gr/chess/xmasmil.html
>>>>>>>>
>>>>>>>>I do NOT know the answer.
>>>>>>>
>>>>>>>[D]8/3p4/3p4/2pPp3/1pPkPp2/1n1p1n2/P2p2P1/3K4 b - - - -
>>>>>>>
>>>>>>>Kiwi can't see it either...
>>>>>>>
>>>>>>> 3/ 9  +7.92  00:00       524  Ng5 axb3 Nxe4
>>>>>>> 4/ 4  +7.92  00:00       579  Ng5 axb3 Nxe4 g3
>>>>>>> 5/ 5  +9.44  00:00      3290  Ng5 axb3 Nxe4 g3 fxg3
>>>>>>> 6/ 7  +9.52  00:00      3998  Ng5 a3 Nxe4
>>>>>>> 7/21     M4  00:00    114504  Ng5 g3 Nh3 axb3 Kc3
>>>>>>
>>>>>>It's a sort of trick question, but there is still a flaw in it.
>>>>>>
>>>>>>Unless I'm missing something, for it to be a Mate in 2 for Black White's last
>>>>>>move had to have been either c2-c4 or e2-e4. After EITHER of these moves, Black
>>>>>>capturing en passant leads to a Mate in 2.
>>>>>>
>>>>>>However, the designation on the page "there is a single answer" is not correct,
>>>>>>because White could have made either of those moves, and therefore there are two
>>>>>>possible responses by Black.
>>>>>>
>>>>>>jm
>>>>>
>>>>>
>>>>> I'm not following you here. How, in the name of all Houdinis, could the
>>>>> last white move be e2-e4???
>>>>>
>>>>> /S
>>>>
>>>>I decided to post the solution after the hint that you give and after
>>>>understanding that the site is very old site and there is no point in keeping
>>>>the solution as a secret.
>>>>
>>>>Of course it cannot be e2-e4 because it means that the white bishop at f1 was
>>>>not captured by a pawn and the position is illegal because black needs too many
>>>>captures to get the pawn structure.
>>>>
>>>>
>>>>Uri
>>>
>>>Indeed, very impressive.
>>>
>>>I found a complete description of the solution (although the board is flipped
>>>such that it is WHITE to Mate in 2) here:
>>>
>>>www.gtryfon.demon.co.uk/bcc/news/dec98news.htm#Christmas%20tree%20puzzle!
>>>
>>>Fun problem!
>>>
>>>jm
>>
>>
>> Yes, and if you think like children do - you'll see in an instant that e2-e4
>> couldn't have been white's last move. If the pawn was on e2 - then Bf1 would
>> never ever gotten out. That's why the Houdini hint ;-)
>>
>> /S
>
>This is still no proof and you need to count number of captures to find that Bf1
>could not be captured not by a pawn.
>
>Uri

 But never forget to first look at a position with the eyes of your inner
 child... That way you can find the creativity.

 /S



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