h#5
8/8/8/8/7k/1r4Q1/8/K7 b - - 0 1
- Kh5 Qxb3 Kg4 Qa2 Kf3 Kb2 Ke2 Kc3+ Kd1 Qd2#
single-piece single-piece:black
Note: the side to move is in check in the diagram.
KQvkr
4 pieces.
- h#6
- longest mate
- h#5
- deepest unique
- 7
- positions at that depth
- h#5
- deepest dual
- h#4.5
- deepest strict dual
- 2,451,242
- positions with a helpmate
- 111,397
- with a unique solution
- 1,892,352
- cells in the plane
- 1,685,698 bytes
- on disk
Deepest unique problems
h#5
8/7Q/7k/8/1r6/8/8/K7 b - - 0 1
- Kg5 Ka2 Kf4 Ka3 Ke3 Kxb4 Kd2 Kb3 Kc1 Qc2#
single-piece single-piece:black nocheck
Note: the side to move is in check in the diagram.
h#5
8/8/8/8/7k/5r1Q/8/1K6 b - - 0 1
- Kg5 Qxf3 Kh4 Qh5+ Kg3 Kc2 Kf2 Kd3 Ke1 Qe2#
switchback single-piece single-piece:black
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.
Only 2 distinct ideas exist at this depth.
h#4.5
6Q1/8/8/8/7k/1r6/8/K7 w - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Qc4+ Kg3 Ka2 Kf2 Kxb3 Ke1 Kc3 Kd1 Qf1#
- Qxb3 Kg4 Qa2 Kf3 Kb2 Ke2 Kc3+ Kd1 Qd2#
h#4.5
8/8/8/7k/8/1r6/2Q5/K7 w - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Ka2 Kg4 Kxb3 Kf3 Qf5+ Ke2 Kc3 Kd1 Qf1#
- Qxb3 Kg4 Qa2 Kf3 Kb2 Ke2 Kc3+ Kd1 Qd2#