h#7
8/8/8/8/8/K1n5/PB6/7k b - - 0 1
- Kg2 Kb4 Kf3 a4 Ke4 a5 Kd5 a6 Kc6 a7 Kb7 Kc5 Ka6 a8=Q#
pure mirror promotion excelsior excelsior:white single-piece single-piece:black nocapture nocheck
KBPvkn
5 pieces.
- h#12
- longest mate
- h#7
- deepest unique
- 101
- positions at that depth
- h#7
- deepest dual
- h#6.5
- deepest strict dual
- 542,142,361
- positions with a helpmate
- 12,823,655
- with a unique solution
- 355,074,048
- cells in the plane
- 312,324,752 bytes
- on disk
Deepest unique problems
h#7
8/7k/8/n6B/8/K7/P7/8 b - - 0 1
- Nb3 axb3 Kh6 b4 Kg5 b5 Kf4 b6 Ke3 b7 Kd2 b8=Q Kc1 Qb2#
pure model ideal promotion excelsior excelsior:white single-piece single-piece:white nocheck
Deepest dual problems
Deepest dual with different first and last moves: h#6.5. The deepest dual overall is h#7, where the two solutions share a first or a last move.
h#6.5
8/8/8/2B5/4k3/8/1n2P3/K7 w - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Bb4 Kd4 e4 Nc4 e5 Nd6 exd6 Kd3 d7 Kc2 d8=Q Kc1 Qd2#
- e3 Kd3 e4 Nc4 e5 Nd6 exd6 Kc4 d7 Kb5 d8=Q Ka6 Qb6#
pure model promotion excelsior excelsior:white single-piece single-piece:white nocheck umnov
h#6.5
8/8/8/8/8/P2nB3/8/2K1k3 w - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Kb1 Nb4 axb4 Ke2 b5 Kd3 b6 Kc4 b7 Kb5 b8=Q+ Ka6 Qb6#
- Kc2 Nb4+ axb4 Ke2 b5 Kf3 b6 Ke4 b7 Kd5 b8=Q Kc4 Qb3#
pure model promotion closed-walk
Note: the side to move is in check in the diagram.
h#6.5
6Bk/8/8/8/8/2n5/1P6/3K4 w - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Kd2 Nb5 b4 Na7 b5 Kg7 b6 Kf6 bxa7 Ke5 a8=Q Kd4 Qd5#
- bxc3 Kg7 c4 Kf6 c5 Ke5 c6 Kd4 c7 Kc3 c8=Q+ Kb2 Qc1#
promotion excelsior excelsior:white single-piece single-piece:white single-piece:black umnov
Note: the side to move is in check in the diagram.