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Dragon Phoenix
Judge Doom

 Posted: Mon Apr 29, 2002 1:13 am    Post subject: 1 ... that Tim Krabbe has put his site back up (see OT). Taken from the Dutch part of his site: Chess Board ```WKd2,WQf5,WRa4,WNc2,BKb1,BQa8,BNc7,BBa3, BBc4,BPa2,BPb2,BPb5,BPd5,BPg4,BPh5``` White to play (from bottom to top) and mate in 5 (Siers, 1959) [This message has been edited by Dragon Phoenix (edited 04-28-2002 09:14 PM).]
ctrlaltdel
Member of the Daedalians

 Posted: Mon Apr 29, 2002 6:50 am    Post subject: 2 huh??? am i missing something again??? white has a mate in two! 1. Nxa3++ Ka1 2. Qb1#
mole
Subterranean Member

 Posted: Mon Apr 29, 2002 6:54 am    Post subject: 3 2... axb1 maybe?
ctrlaltdel
Member of the Daedalians

 Posted: Mon Apr 29, 2002 7:27 am    Post subject: 4 heck thats right... and it even says white playing from bottom up, DUHH
borschevsky
Chessnut

 Posted: Mon Apr 29, 2002 2:28 pm    Post subject: 5 Yes, but if axb1=Q then 3.Nc2 is mate, no? However: 2..axb1=N and white has no mate.
borschevsky
Chessnut

 Posted: Mon Apr 29, 2002 2:33 pm    Post subject: 6 Well, Qf1 would be mate right now if it wasn't for the Bc4, so maybe RxB to remove the bishop, or just Qf2 to try for Qe1# next. But in both cases black can just go a1 to open a hole on a2.
borschevsky
Chessnut

 Posted: Mon Apr 29, 2002 2:49 pm    Post subject: 7 Oh, what about... 1. Qf2 a1=Q (to stop Qe1#) 2. Qf5! to re-threaten discoveries by the knight If black does nothing constructive, then 3. Nb4+ and Qc2# (black can waste a move with Bd3 but white is in time) 2...Qa2 3.Nxa3+ Ka1 4.Qb1! Qxb1 5.Nc2# I don't think I've checked all the variations, but that has to be right. It's too pretty to have a refutation .
Dragon Phoenix
Judge Doom

 Posted: Mon Apr 29, 2002 2:54 pm    Post subject: 8 Yes, that's correct. Well done - as expected! The theme is that the black pawn does not promote but degrade to a queen. When the new black queen comes to a2 where the pawn came from, it is less powerful than the pawn - it cannot promote to a knight.
ctrlaltdel
Member of the Daedalians

 Posted: Mon Apr 29, 2002 9:58 pm    Post subject: 9 heres one variation... 1. Qf2! a1N 2. Qe1+ Ka2 3. Qxa1+ Kb3 4. Rxa3+ Qxa3 5. Qxa3# [This message has been edited by ctrlaltdel (edited 04-29-2002 05:58 PM).]
Coyote

 Posted: Tue Apr 30, 2002 12:26 am    Post subject: 10 Believe it or not, I even 'read' the in het Nederlands section of Tim Krabbe's site (after all Chess is a universal language). That's why I didn't bother sticking my nose in this one. Incidentally, the 'loss of promotion rights' idea has been done before. This one is an especially nice example though.
Coyote

 Posted: Tue Apr 30, 2002 12:30 am    Post subject: 11 Oops, just scrolled back up and checked the date of the problem's publication...disregard that 'has been done before' bit.
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