h#6
K7/1p6/8/8/8/8/4Q3/5k2 b - - 0 1
- Kg1 Kxb7 Kh1 Kc6 Kg1 Kd5 Kh1 Ke4 Kg1 Kf3 Kh1 Qg2#
pure model ideal switchback single-piece single-piece:black nocheck
Note: the side to move is in check in the diagram.
KQvkp
4 pieces.
- h#7
- longest mate
- h#6
- deepest unique
- 4
- positions at that depth
- h#6
- deepest dual
- h#4.5
- deepest strict dual
- 8,294,413
- positions with a helpmate
- 466,854
- with a unique solution
- 5,548,032
- cells in the plane
- 5,639,394 bytes
- on disk
Deepest unique problems
h#6
K7/1p6/8/8/6Q1/7k/8/8 b - - 0 1
- Kh2 Kxb7 Kh1 Kc6 Kh2 Kd5 Kh1 Ke4 Kh2 Kf3 Kh1 Qg2#
pure model ideal switchback single-piece single-piece:black nocheck
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#6, where the two solutions share a first or a last move.
Only 2 distinct ideas exist at this depth.
h#4.5
8/8/8/7k/8/p2Q4/8/K7 w - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Kb1 Kg4 Qg6+ Kf3 Kc2 Kf2 Kd3 Ke1 Qg1#
- Qxa3 Kg4 Qa2 Kf3 Kb2 Ke2 Kc3+ Kd1 Qd2#
h#4.5
8/8/7k/5Q2/8/2p5/1K6/8 w - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Kc1 c2 Kd2 c1=R Ke3 Rc7 Kf4 Rh7 Qg5#
- Kxc3 Kg7 Kd4 Kh8 Ke5 Kg8 Kf6 Kf8 Qc8#
pure model ideal mirror promotion underpromotion self-block single-piece single-piece:black nocheck umnov
Note: the side to move is in check in the diagram.