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Jazz Writer Beginner
Joined: 25 Nov 2008 Posts: 3
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Posted: Tue Nov 25, 2008 3:26 pm Post subject: problem 4040 misses an alternate solution |
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problem 4040 overlooks another solution. After white sacrifices his bishop, queen and newly queened pawn to black's bishop:
1. a8-g2 h1:g2
2. d1-h1 g2:h1
3. a7 h1-f3
4. a8 (Q) f3:a8
the following moves will avoid the stalemate:
5. c1-e1 / a8-c6
6. a2-b4
Regardless of where the black bishop moves, one of the two white rooks will succeed in obtaining a back rank mate, as the bishop must move and can no longer guard both a8 and e8 from the rooks. Also, there is no way for the bishop to check the king immediately, nor for the black king to free itself.
For example if 6.... c6-e4, 7 e1-e7 and the bishop can't successfully hold both 8th rank squares.
I'd love to get a pm if someone has spotted a flaw in my reasoning. I haven't been playing much lately but have found some of these chess problems to be of interest.
Hopefully, my notation is correct. I still use the old-fashioned English descriptive, which is harder to keep up with but gives me a better idea of what's happening in a game at a glance. |
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888 Expert

Joined: 17 Dec 2007 Posts: 35 Location: China
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Posted: Tue Nov 25, 2008 11:14 pm Post subject: |
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Well, black does not need to go Bc6 to e4, there is a better defence for black: 1...Ba4!! |
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888 Expert

Joined: 17 Dec 2007 Posts: 35 Location: China
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Posted: Tue Nov 25, 2008 11:21 pm Post subject: |
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Sorry, after further investigation, I will say your are right, after 1...Ba4!, white can pushes d pawn to force bishop go to d7. |
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papadoble Master
Joined: 15 Jan 2006 Posts: 85 Location: Yerres, France
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Posted: Wed Nov 26, 2008 5:07 am Post subject: |
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5.Re1? Be4!, similarly 5.Rf1? Bf3!
This composition is very interesting and not so easy to solve, e.g. 2.a7? is tempting but leads to nothing after 2...~ 3.a8=Q+ Bxa8 4.Qh1 Bxh1 because the c1 square is not cleared.
You may also comment on problems directly on the relevant problem pages, we are a few to track comments on http://www.chessproblems.com/rss/comments.php
Btw welcome  _________________ "Si tu vois un bon coup, ne le joue pas!!" - Philippe Bichu (after Em. Lasker) |
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Jazz Writer Beginner
Joined: 25 Nov 2008 Posts: 3
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Posted: Sat Nov 29, 2008 11:10 am Post subject: |
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The problem resulted from the flawed Black move 5... Bc6
that automatically followed in response to my 5. Re1.
I agree that 5... Be4 forces the stalemate, as does 5 Rf1 Bf3.
There must be a bug in the program, as my move still wins after 5...Bc6? There is no stopping a back rank mate. |
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888 Expert

Joined: 17 Dec 2007 Posts: 35 Location: China
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Posted: Sat Nov 29, 2008 6:42 pm Post subject: |
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But can't white goes 6.Ra8+! to win? Because the a7 pawn is not longer on the board. |
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papadoble Master
Joined: 15 Jan 2006 Posts: 85 Location: Yerres, France
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Posted: Sun Nov 30, 2008 1:38 am Post subject: |
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There is no bug in the program because there is no program for endgame studies (only for #1/2/3).
The wrong reply 5...Bc6? to 5.Re1? had been entered by puzzle setter.
The solution is now edited. _________________ "Si tu vois un bon coup, ne le joue pas!!" - Philippe Bichu (after Em. Lasker) |
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