change log for P1231029 (close)
date | time | user | object | table | field | type | old | new |
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2012-01-25 | 18:41:17 | Alain 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. | 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. |
2012-01-25 | 18:39:44 | Alain Brobecker | Promotion | refkey | add | |||
2012-01-25 | 18:32:54 | Alain Brobecker | Variant Chess 43 | refsrc | add | |||
2012-01-25 | 18:32:42 | Alain Brobecker | Fairies | refgen | add | |||
2012-01-25 | 18:32:42 | Alain Brobecker | wKb4 wLc7 wBa3a4b7 sKa6 sDa8 sBh2a7 | position | add | |||
2012-01-25 | 18:32:42 | Alain Brobecker | Noam D. Elkies | refaut | add | |||
2012-01-25 | 18:32:42 | Alain Brobecker | P1231029 | problems | fcooked | update | F | |
2012-01-25 | 18:32:42 | Alain Brobecker | P1231029 | problems | cplus | update | F | |
2012-01-25 | 18:32:42 | Alain Brobecker | P1231029 | problems | award | update | Prize | |
2012-01-25 | 18:32:42 | Alain Brobecker | P1231029 | problems | comment | update | Variant Chess Theme Tourney asking for problems with the L77 leaper. | |
2012-01-25 | 18:32:42 | Alain 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. | |
2012-01-25 | 18:32:42 | Alain 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. | |
2012-01-25 | 18:32:41 | Alain Brobecker | P1231029 | problems | add |