Number of ways to place n nonattacking composite pieces rook + rider[2,4] on an n X n chessboard.
A189855
Number of ways to place n nonattacking composite pieces rook + rider[2,4] on an n X n chessboard.
Terms
- a(0) =1a(1) =2a(2) =6a(3) =24a(4) =60a(5) =208a(6) =1184a(7) =7840a(8) =36036a(9) =209664a(10) =1395480a(11) =10996728a(12) =83573220a(13) =723835856a(14) =7132494776a(15) =77976981216a(16) =790552134804
External references
- oeis: A189855