h#7.5
8/7k/8/8/8/7r/1K5P/n7 w - - 0 1
- Ka2 Ra3+ Kxa3 Kg6 h4 Kf5 h5 Ke4 h6 Kd3 h7 Kc2 h8=Q Kb1 Qb2#
KPvkrn
5 pieces.
- h#9.5
- longest mate
- h#7.5
- deepest unique
- 50
- positions at that depth
- h#7.5
- deepest dual
- h#6.5
- deepest strict dual
- 523,706,271
- positions with a helpmate
- 6,911,613
- with a unique solution
- 355,074,048
- cells in the plane
- 214,826,368 bytes
- on disk
Deepest unique problems
h#7.5
8/7k/8/8/8/8/r2n2P1/K7 w - - 0 1
- Kxa2 Kg6 Ka3 Kf5 g4+ Ke4 g5 Kd3 g6 Kc2 g7 Kb1 g8=Q Ka1 Qa2#
promotion excelsior excelsior:white single-piece single-piece:black
Note: the side to move is in check in the diagram; the solution begins with a capture.
h#7.5
7k/8/8/8/1rn5/7P/8/1K6 w - - 0 1
- Ka1 Kg7 h4 Kf6 h5 Ke5 h6 Kd4 h7 Kc3 h8=Q+ Kb3 Qh2 Ka3 Qa2#
promotion single-piece single-piece:black nocapture
Note: the side to move is in check in the diagram.
Deepest dual problems
Deepest dual with different first and last moves: h#6.5. The deepest dual overall is h#7.5, where the two solutions share a first or a last move.
h#6.5
8/8/8/8/4r3/2k1P3/5n2/K7 w - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Kb1 Rd4 e4 Ng4 e5 Nf6 exf6 Kd2 f7 Kd1 f8=Q Rd2 Qf1#
- Ka2 Rb4 e4 Ng4 e5 Nf6 exf6 Rb5 f7 Kb4 f8=Q+ Ka4 Qa3#
h#6.5
8/8/8/8/1k6/3r4/3P4/Kn6 w - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Ka2 Rb3 d4 Na3 d5 Nb5 d6 Nc7 dxc7 Ka4 c8=Q Rb4 Qa6#
- Kb2 Ra3 d4 Nc3 d5 Nb5 d6 Nc7 dxc7 Ra5 c8=Q Ka4 Qc4#
set-play promotion excelsior excelsior:white self-block nocheck
h#6.5
8/5k2/8/8/6r1/6P1/8/nK6 w - - 0 1
Two solutions, with different first and last moves (2 starts, 2 ends).
- Kc1 Rh4 gxh4 Ke6 h5 Kd5 h6 Kc4 h7 Kb3 h8=Q Ka2 Qb2#
- Kxa1 Rb4 g4 Ke6 g5 Kd5 g6 Kc4 g7 Kb3 g8=Q+ Ka3 Qa2#