Number of ways to arrange 7 nonattacking triangular rooks on an nXnXn triangular grid.

A193985

Number of ways to arrange 7 nonattacking triangular rooks on an nXnXn triangular grid.

Terms

    a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =0a(6) =0a(7) =0a(8) =0a(9) =28a(10) =4842a(11) =104448a(12) =1127473a(13) =8147469a(14) =44813100a(15) =201616740a(16) =776296572a(17) =2638333236a(18) =8091512680a(19) =22767562704a(20) =59525327634a(21) =146063694310a(22) =339101167392a(23) =749761416480

External references