Number of ways to place n nonattacking composite pieces queen + rider[2,4] on an n X n chessboard.

A189877

Number of ways to place n nonattacking composite pieces queen + rider[2,4] on an n X n chessboard.

Terms

    a(0) =1a(1) =0a(2) =0a(3) =2a(4) =0a(5) =0a(6) =0a(7) =0a(8) =0a(9) =4a(10) =56a(11) =172a(12) =680a(13) =1348a(14) =6576a(15) =34568a(16) =107624a(17) =413760a(18) =1697288a(19) =8035558a(20) =37441416a(21) =192483420a(22) =1115143224

External references