change log for P1231029 (close)

datetimeuserobjecttablefieldtypeoldnew
2012-01-2518:41:17Alain Brobecker P1231029 problems solution  update1.bxa8=Q? h1=Q 2.QxQ stalemate. 1.bxa8=L02+ Kb7 2.Bxh2 Kxa8 leads to a book draw with a rook's pawn and the wrong bishop. 1.bxa8=L16 h1=Q? 2.L16g7+ wins and 1... h1=L63+ 2.Kb3 traps the L63. However 1... h1=L16! leaves the two leapers mutually trapped in what's essentially the same old draw. So finally we turn to the least useful leaper: 1.bxa8=L77! Kb7 2.L77h1! Kxc7 and the L77's control of a8 turns out to be just enough to let white promote eventually though only by way of careful K-play and no fewer than 4 positions of mutual zugzwang: 3.Ka5! (threat 4.Ka6 Kb8 5.a5) Kb7 4.Kb5! (mutual zugzwang) a6+ 5.Kc5 (mzz) Kc7 6.a5 (mzz) Kb7 7.Kd6 Kb8 (or Ka7 8.Kc6!, avoiding 8.Kc7? stalemate) 8.Kc6 Ka7 9.a4! (final and decisive mzz) and wins. 1.bxa8=Q? h1=Q 2.QxQ stalemate. 1.bxa8=L02+? Kb7 2.Bxh2 Kxa8 leads to a book draw with a rook's pawn and the wrong bishop. 1.bxa8=L16 h1=Q? 2.L16g7+ wins and 1... h1=L63+ 2.Kb3 traps the L63. However 1... h1=L16! leaves the two leapers mutually trapped in what's essentially the same old draw. So finally we turn to the least useful leaper: 1.bxa8=L77! Kb7 2.L77h1! Kxc7 and the L77's control of a8 turns out to be just enough to let white promote eventually though only by way of careful K-play and no fewer than 4 positions of mutual zugzwang: 3.Ka5! (threat 4.Ka6 Kb8 5.a5) Kb7 4.Kb5! (mutual zugzwang) a6+ 5.Kc5 (mzz) Kc7 6.a5 (mzz) Kb7 7.Kd6 Kb8 (or Ka7 8.Kc6!, avoiding 8.Kc7? stalemate) 8.Kc6 Ka7 9.a4! (final and decisive mzz) and wins. 
2012-01-2518:39:44Alain Brobecker Promotion refkey   add  
2012-01-2518:32:54Alain Brobecker Variant Chess 43  refsrc   add  
2012-01-2518:32:42Alain Brobecker Fairies refgen   add  
2012-01-2518:32:42Alain Brobecker wKb4 wLc7 wBa3a4b7 sKa6 sDa8 sBh2a7 position   add  
2012-01-2518:32:42Alain Brobecker Noam D. Elkies refaut   add  
2012-01-2518:32:42Alain Brobecker P1231029 problems fcooked  update 
2012-01-2518:32:42Alain Brobecker P1231029 problems cplus  update 
2012-01-2518:32:42Alain Brobecker P1231029 problems award  update Prize 
2012-01-2518:32:42Alain Brobecker P1231029 problems comment  update Variant Chess Theme Tourney asking for problems with the L77 leaper. 
2012-01-2518:32:42Alain Brobecker P1231029 problems solution  update 1.bxa8=Q? h1=Q 2.QxQ stalemate. 1.bxa8=L02+ Kb7 2.Bxh2 Kxa8 leads to a book draw with a rook's pawn and the wrong bishop. 1.bxa8=L16 h1=Q? 2.L16g7+ wins and 1... h1=L63+ 2.Kb3 traps the L63. However 1... h1=L16! leaves the two leapers mutually trapped in what's essentially the same old draw. So finally we turn to the least useful leaper: 1.bxa8=L77! Kb7 2.L77h1! Kxc7 and the L77's control of a8 turns out to be just enough to let white promote eventually though only by way of careful K-play and no fewer than 4 positions of mutual zugzwang: 3.Ka5! (threat 4.Ka6 Kb8 5.a5) Kb7 4.Kb5! (mutual zugzwang) a6+ 5.Kc5 (mzz) Kc7 6.a5 (mzz) Kb7 7.Kd6 Kb8 (or Ka7 8.Kc6!, avoiding 8.Kc7? stalemate) 8.Kc6 Ka7 9.a4! (final and decisive mzz) and wins. 
2012-01-2518:32:42Alain Brobecker P1231029 problems stip  update White to move and win. Pawns may promote to any of the 35 leapers from L01 to L77 in addition to the usual QRBN. 
2012-01-2518:32:41Alain Brobecker P1231029 problems   add