T(n,k) is the number of ways to arrange k nonattacking triangular rooks on an nXnXn triangular grid.
A193986
T(n,k) is the number of ways to arrange k nonattacking triangular rooks on an nXnXn triangular grid.
Terms
- a(0) =1a(1) =0a(2) =3a(3) =0a(4) =0a(5) =6a(6) =0a(7) =0a(8) =3a(9) =10a(10) =0a(11) =0a(12) =0a(13) =15a(14) =15a(15) =0a(16) =0a(17) =0a(18) =2a(19) =45a(20) =21a(21) =0a(22) =0a(23) =0a(24) =0a(25) =23a(26) =105a(27) =28a(28) =0a(29) =0
External references
- oeis: A193986