Number of chess diagrams that can be obtained in exactly one way in n plies and cannot be obtained in fewer plies. This is also the number of dual-free shortest proof games in n plies.

A209080

Number of chess diagrams that can be obtained in exactly one way in n plies and cannot be obtained in fewer plies. This is also the number of dual-free shortest proof games in n plies.

Terms

    a(0) =1a(1) =20a(2) =400a(3) =1702a(4) =8659a(5) =49401a(6) =287740a(7) =1934794a(8) =11569093a(9) =65443733a(10) =360231372a(11) =1872156836

External references