h#7.5
8/K7/8/8/8/8/3P4/2q4k w - - 0 1
- d4 Kg2 d5 Kf3 d6 Ke4 d7 Kd5 d8=Q+ Kc6 Qd5+ Kc7 Ka6 Kb8 Qb7#
promotion excelsior excelsior:white closed-walk single-piece single-piece:black nocapture umnov
KPvkq
4 pieces.
- h#9
- longest mate
- h#7.5
- deepest unique
- 32
- positions at that depth
- h#7.5
- deepest dual
- h#6.5
- deepest strict dual
- 8,342,799
- positions with a helpmate
- 75,863
- with a unique solution
- 5,548,032
- cells in the plane
- 4,893,098 bytes
- on disk
Deepest unique problems
h#7.5
1q6/8/1K6/8/8/8/2P5/7k w - - 0 1
- Ka6 Kg2 c4 Kf3 c5 Ke4 c6 Kd5 c7 Kc6 Ka5 Kb7 c8=Q+ Ka7 Qa6#
promotion excelsior excelsior:white single-piece single-piece:black nocapture umnov
Note: the side to move is in check in the diagram.
Deepest dual problems
Deepest dual with different first and last moves: h#6.5. The deepest dual overall is h#7.5, where the two solutions share a first or a last move.
h#6.5
5k2/8/8/8/7q/8/7P/3K4 w - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Kc1 Qa4 h4 Ke7 h5 Kd6 h6 Kc5 h7 Kb4 h8=Q Ka3 Qb2#
- Kc2 Qg5 h4 Ke7 hxg5 Kd6 g6 Kc5 g7 Kb4 g8=Q Ka3 Qb3#
pure model ideal promotion excelsior excelsior:white self-block nocheck umnov
h#6.5
8/8/1K6/8/8/8/2P1q3/5k2 w - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Kc7 Qb5 c4 Ke2 cxb5 Kd3 b6 Kc4 b7 Kb5 b8=Q+ Ka6 Qb6#
- c4 Ke1 c5 Kd2 c6 Kc3 c7 Kb4 Kc6 Ka5 c8=R Ka6 Ra8#
pure model mirror promotion underpromotion excelsior excelsior:white closed-walk single-piece single-piece:black