Helpmate tablebases Every solution to every position, precomputed.

← all materials

KRvkqb

5 pieces.

h#7.5
longest mate: h#6.5
deepest unique: 1
positions at that depth: h#6
deepest dual: h#5.5
deepest strict dual: 140,054,411
positions with a helpmate: 4,495,889
with a unique solution: 121,110,528
cells in the plane: 78,081,597 bytes
on disk

Deepest unique problems

Only one position exists at this depth.

h#6.5

8/8/5k2/3R4/8/bq6/8/1K6 w - - 0 1

Ka1 Bb2+ Kb1 Be5+ Kc1 Kg5 Kd2 Kh4 Ke2 Bc3 Kf3 Kh3 Rh5#

pure model mirror switchback nocapture

Note: the side to move is in check in the diagram.

Published as Sheglow (1998)

Sheglow, Wiktor S. — Suomen Tehtäväniekat, No. (312), 05-06/1998

Deepest dual problems

Deepest dual with different first and last moves: h#5.5. The deepest dual overall is h#6, where the two solutions share a first or a last move.

h#5.5

8/8/8/1q5k/8/b7/R7/K7 w - - 0 1

Two solutions, with different first and last moves (2 starts, 2 ends).

Rb2 Kg4 Kb1 Kf3 Kc2 Ke2 Kc3+ Kd1 Re2 Kc1 Re1#
Rxa3 Kg4 Ra4+ Kf3 Rb4 Ke2 Kb2 Kd1 Kc3 Qe2 Rb1#

pure model ideal mirror self-block single-piece single-piece:black umnov

h#5.5

4k3/8/8/8/b7/8/3q4/1KR5 w - - 0 1

Two solutions, with different first and last moves (2 starts, 2 ends).

Rd1 Qc1+ Kxc1 Kf7 Kd2 Kg6 Ke3 Kh5 Kf4 Kh4 Rh1#
Rc2 Qc1+ Kxc1 Kf7 Kd2 Kg6 Ke3 Kh5 Kf4 Kh4 Rh2#

pure model mirror umnov

h#5.5

5k2/8/8/8/8/8/3q4/RK3b2 w - - 0 1

Two solutions, with different first and last moves (2 starts, 2 ends).

Ra2 Qc2+ Kxc2 Bd3+ Kxd3 Kg7 Ke4 Kh6 Kf5 Kh5 Rh2#
Ra3 Qc2+ Kxc2 Bd3+ Kxd3 Kg7 Ke4 Kh6 Kf5 Kh5 Rh3#

set-play pure model ideal mirror