h#6.5
6k1/5R2/8/8/8/1p6/2q5/1K6 w - - 0 1
- Ka1 Qb2+ Kxb2 Kh8 Kc3 b2 Kd4 b1=R Ke5 Rh1 Kf6 Rh7 Rf8#
pure model ideal promotion underpromotion self-block umnov
Note: the side to move is in check in the diagram.
KRvkqp
5 pieces.
- h#7.5
- longest mate
- h#6.5
- deepest unique
- 17
- positions at that depth
- h#6.5
- deepest dual
- h#6
- deepest strict dual
- 443,855,743
- positions with a helpmate
- 16,608,068
- with a unique solution
- 355,074,048
- cells in the plane
- 215,437,828 bytes
- on disk
Deepest unique problems
h#6.5
8/8/7k/6R1/p7/8/K7/q7 w - - 0 1
- Kxa1 Kh7 Kb2 a3+ Kc3 a2 Kd4 a1=R Ke5 Ra8 Kf6 Rg8 Rh5#
pure model ideal promotion underpromotion self-block
Note: the side to move is in check in the diagram; the solution begins with a capture.
h#6.5
q7/K1p5/8/8/8/6R1/8/7k w - - 0 1
- Kxa8 c5 Kb7 c4 Kc6 c3 Kd5 c2 Ke4 c1=R Kf3 Rg1 Rh3#
pure model ideal promotion underpromotion excelsior excelsior:black self-block single-piece single-piece:black 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#6. The deepest dual overall is h#6.5, where the two solutions share a first or a last move.
h#6
7k/8/6R1/8/p7/8/3q4/K7 b - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Qh6 Kb2 a3+ Kc3 a2 Kd4 a1=R Ke5 Ra8 Kf6 Rg8 Rxh6#
- Qb2+ Kxb2 a3+ Kc3 a2 Kd4 a1=R Ke5 Ra8 Kf6 Rg8 Rh6#
h#6
K7/3q4/8/4p3/8/6R1/8/7k b - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Qh3 Kb7 e4 Kc6 e3 Kd5 e2 Ke4 e1=R+ Kf3 Rg1 Rxh3#
- Qb7+ Kxb7 e4 Kc6 e3 Kd5 e2 Ke4 e1=R+ Kf3 Rg1 Rh3#
h#6
7k/5R2/8/7p/1q6/8/8/K7 b - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Qf8 Kb2 h4 Kc3 h3 Kd4 h2 Ke5 h1=R Kf6 Rh7 Rxf8#
- Qb2+ Kxb2 h4 Kc3 h3 Kd4 h2 Ke5 h1=R Kf6 Rh7 Rf8#