h#6
K7/1p6/8/8/8/8/4Q3/6kQ b - - 0 1
- Kxh1 Kxb7 Kg1 Kc6 Kh1 Kd5 Kg1 Ke4 Kh1 Kf3 Kg1 Qg2#
switchback single-piece single-piece:black pendulum nocheck
Note: the side to move is in check in the diagram; the solution begins with a capture.
KQQvkp
5 pieces.
- h#7
- longest mate
- h#6
- deepest unique
- 6
- positions at that depth
- h#6
- deepest dual
- h#4
- deepest strict dual
- 215,518,695
- positions with a helpmate
- 36,190,809
- with a unique solution
- 355,074,048
- cells in the plane
- 186,481,161 bytes
- on disk
Deepest unique problems
h#6
K7/1p6/8/8/6Q1/8/7Q/7k b - - 0 1
- Kxh2 Kxb7 Kh1 Kc6 Kh2 Kd5 Kh1 Ke4 Kh2 Kf3 Kh1 Qg2#
pure model ideal switchback single-piece single-piece:black pendulum nocheck
Note: the side to move is in check in the diagram; the solution begins with a capture.
Deepest dual problems
Deepest dual with different first and last moves: h#4. The deepest dual overall is h#6, where the two solutions share a first or a last move.
h#4
8/5p2/6Qk/8/8/K7/Q7/8 b - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Kxg6 Kb4 Kg7 Kc5 Kf8 Kd6 Ke8 Qa8#
- fxg6 Kb4 Kg7 Kc5 Kf8 Kd6 Ke8 Qg8#
pure model ideal mirror single-piece single-piece:black nocheck
Note: the side to move is in check in the diagram; the solution begins with a capture.
h#4
8/2K5/3Q4/8/8/6p1/5Q2/5k2 b - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Kxf2 Kd7 Kg2 Ke6 Kh3 Kf5 Kh4 Qh6#
- gxf2 Kd7 Kg2 Ke6 Kh3 Kf5 Kh4 Qh2#
pure model mirror single-piece single-piece:black nocheck
Note: the side to move is in check in the diagram; the solution begins with a capture.
h#4
8/5p2/6Qk/8/2Q5/1K6/8/8 b - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Kxg6 Kb4 Kg7 Kc5 Kf8 Kd6 Ke8 Qc8#
- fxg6 Kb4 Kg7 Kc5 Kf8 Kd6 Ke8 Qg8#
pure model mirror single-piece single-piece:black nocheck
Note: the side to move is in check in the diagram; the solution begins with a capture.