From: davewood@bruno.cs.colorado.edu (David Rex Wood)
Subject: Re: Sextupled pawns Re: Quadruple pawns 
Keywords: sextupled a-pawns!?
Organization: University of Colorado, Boulder
Date: Thu, 28 Jan 1993 23:12:09 GMT

In article <1993Jan28.222556.27575@colorado.edu> davewood@bruno.cs.colorado.edu (David Rex Wood) writes:
>In article <1993Jan28.221646.27266@colorado.edu> davewood@bruno.cs.colorado.edu (David Rex Wood) writes:
>>In article <1993Jan26.224738.19839@husc3.harvard.edu> elkies@ramanujan.harvard.edu (Noam Elkies) writes:
>>>In article <1993Jan26.054608.2373@noose.ecn.purdue.edu>
>>>achar@ecn.purdue.edu writes:
>>>>Another one of those "once in a while" games.
>>>>[Amusing ICS games with quadrupled Black e-pawns omitted]
>>>
>>>...which reminds me:
>>>
>>>White: Ke1, Ra1, pawns a2,a3,a4,a5,a6,a7
>>>Black: Ka8
>>>
>>>k _ . _ . _ . _
>>>P . _ . _ . _ .
>>>P _ . _ . _ . _
>>>P . _ . _ . _ .
>>>P _ . _ . _ . _
>>>P . _ . _ . _ .
>>>P _ . _ . _ . _
>>>R . _ . K . _ .
>>>
>>>Two puzzles:
>>>
>>>i. (easy) White to play and mate in 8.
>>>
>>>ii. (considerably harder) is the position, and the solution, legal?
>>>[That is, could this arise by legal --- albeit ridiculous --- play
>>>from the initial position?]
>>>
>>>--Noam D. Elkies (elkies@zariski.harvard.edu)
>>>  Dept. of Mathematics, Harvard University
>>
>>
>>-- 
>>-------------------------------------------------------------------------------
>>David Rex Wood -- davewood@cs.colorado.edu -- University of Colorado at Boulder
>>-------------------------------------------------------------------------------
>
>Strange, my response disappeared.  Lets try this again...
>
>In article <1993Jan26.224738.19839@husc3.harvard.edu> elkies@ramanujan.harvard.edu (Noam Elkies) writes:
>>In article <1993Jan26.054608.2373@noose.ecn.purdue.edu>
>>achar@ecn.purdue.edu writes:
>>>Another one of those "once in a while" games.
>>>[Amusing ICS games with quadrupled Black e-pawns omitted]
>>
>>...which reminds me:
>>
>>White: Ke1, Ra1, pawns a2,a3,a4,a5,a6,a7
>>Black: Ka8
>>
>>k _ . _ . _ . _
>>P . _ . _ . _ .
>>P _ . _ . _ . _
>>P . _ . _ . _ .
>>P _ . _ . _ . _
>>P . _ . _ . _ .
>>P _ . _ . _ . _
>>R . _ . K . _ .
>>
>>Two puzzles:
>>
>>i. (easy) White to play and mate in 8.
>>
>>ii. (considerably harder) is the position, and the solution, legal?
>>[That is, could this arise by legal --- albeit ridiculous --- play
>>from the initial position?]
>>
>>--Noam D. Elkies (elkies@zariski.harvard.edu)
>>  Dept. of Mathematics, Harvard University
>
>Okay, I sat through a couple classes not paying attention and playing with
>number ii.  Here is (I think) the optimal solution...
>
>
>First, YES, it can be done.
>The are 15 (5+4+3+2+1) required pawn captures for white which corresponds
>to the number of pieces black has to lose.  Further important is the fact
>that white has 9 pieces to waste.  At some point, each of black's 15 pieces
>needs to move to the lower left side of the board, like this:
>
>K-------
>B-------
>BB------
>BBB-----
>BBBB----
>BBBBB---
>--------
>--------  (Where B is a black piece, K is black's king)
>
>To make this work we can either promote 3 of black's pawns (easy solution) or
>promote only one and move the other two across diagonally.  This is what I
>did and solved the problem in 39 moves.  I think this is optimal based on
>the following:
>
>Piece		Number of moves to get to a place it can be captured
>------------------------------------------------------------
>a pawn		1 (to make life easier on QR)
>b-e pawns	1+1+2+3 = 7
>f pawn		5 (=Q) +2 = 7
>g,h pawns	4 (captures) each = 8
>QR		1
>QN		1
>QB		2 (doing it in 1 conflicts with QN)
>Q		2 (doing it in 1 conflicts with a-pawn, b-pawn, or h-pawn)
>K		4
>KB		1
>KN		3
>KR		2
>
>So, while it is conceivable (loosely) that we could knock off 4 more moves
>for black (a pawn, QB, Q and K (could castle)) all of these would cause
>other numbers to increase.  I'm pretty sure 39 is as good as it gets.
>
>To make sure I wasn't cheating, I played it through.  This is certainly not
>the only solution and its not even all that pretty -- but it works.
>
>1. g4  a5
>2. g5  Ra7
>3. g6  hxg6
>4. Bh3  Na6
>5. Bf5  gxf5
>6. Nc3  b6
>7. Ne4  fxe4
>8. Nf3  Nf6
>9. Ne5  Nd5
>10. Nd3  exd3
>11. exd3  e5
>12. Qf3  e4
>13. Qf6  gxf6
>14. h4  Ba3
>15. bxa3  c5
>16. Bb2  e3
>17. Be5  fxe5
>18. Rb1  f5
>19. Rb3  Ndb4
>20. h5  Rxh5
>21. Rh4  f4
>22. Rc3  f3
>23. Rd4  exd4
>24. fxe3  dxc3
>25. dxc3  d5
>26. cxb4  d4
>27. bxa5  Qd5
>28. exd4  Qb3
>29. dxc5  Be6
>30. cxb6  Bc4
>31. cxb3  f2+
>32. Kd2  Rb5
>33. dxc4  f1Q
>34. cxb5  Kd8
>35. bxa6  Qf4
>36. Kd1  Qa4
>37. Ke1  Kc8
>38. bxa4  Kb8
>39. bxa7+  Ka8
>-- 
>-------------------------------------------------------------------------------
>David Rex Wood -- davewood@cs.colorado.edu -- University of Colorado at Boulder
>-------------------------------------------------------------------------------


-- 
-------------------------------------------------------------------------------
David Rex Wood -- davewood@cs.colorado.edu -- University of Colorado at Boulder
-------------------------------------------------------------------------------
Newsgroups: rec.games.chess