h#5
8/8/7k/8/8/b5Q1/8/K7 b - - 0 1
- Kh5 Qxa3 Kg4 Qa2 Kf3 Kb2 Ke2 Kc3+ Kd1 Qd2#
KQvkb
4 pieces.
- h#6
- longest mate
- h#5
- deepest unique
- 64
- positions at that depth
- h#5
- deepest dual
- h#4.5
- deepest strict dual
- 2,581,569
- positions with a helpmate
- 129,760
- with a unique solution
- 1,892,352
- cells in the plane
- 1,864,913 bytes
- on disk
Deepest unique problems
h#5
8/8/7k/8/8/4Q3/8/K2b4 b - - 0 1
- Kh5 Kb2 Kg4 Qg5+ Kf3 Kc3 Kf2 Kd3 Ke1 Qg1#
single-piece single-piece:black nocapture
Note: the side to move is in check in the diagram.
h#5
8/5k2/4Q3/8/8/1b6/8/1K6 b - - 0 1
- Kg7 Kc1 Bc2 Kd2 Bg6 Ke3 Kh6 Kf4 Kh5 Qh3#
Note: the side to move is in check in the diagram.
Deepest dual problems
Deepest dual with different first and last moves: h#4.5. The deepest dual overall is h#5, where the two solutions share a first or a last move.
h#4.5
8/8/8/6k1/8/2b2Q2/8/K7 w - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Kb1 Kh4 Qh5+ Kg3 Kc2 Kf2 Kd3 Ke1 Qe2#
- Qxc3 Kf4 Qf6+ Ke3 Kb2 Ke2 Kc3 Kd1 Qf1#
pure model ideal mirror single-piece single-piece:black
Note: the side to move is in check in the diagram.
h#4.5
4k3/8/8/8/b7/2Q5/8/1K6 w - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Kc1 Kf7 Kd2 Kg6 Ke3 Kh5 Kf4 Kh4 Qh8#
- Kb2 Kd7 Qg7+ Kc6 Kc3 Kb6 Kc4 Ka5 Qa7#
h#4.5
4k3/8/8/6b1/8/8/8/2KQ4 w - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Kc2 Kf7 Kd3 Kg6 Ke2 Kh5 Kf3 Kh4 Qh1#
- Qd2 Kf7 Kd1 Kg6 Ke2 Kh5 Kf3 Kh4 Qh2#
pure model ideal single-piece single-piece:black nocapture nocheck
Note: the side to move is in check in the diagram.