A204432 Permanent of the n-th principal submatrix of A204431.

2, 1, 9, 40, 132, 1032, 7824, 51912, 530712, 5619456, 53529984, 707802624, 9591229440, 119716185600, 1938416832000, 32061464064000, 496487584512000, 9509523337728000, 185772505605120000, 3434389946233344000

Offset: 1

Author

Clark Kimberling, Jan 15 2012

Keywords

• nonn

Crossrefs

Cf. A204231, A204263.

Programs

Mathematica

f[i_, j_] := Mod[2 i + 2 j + 1, 3];
m[n_] := Table[f[i, j], {i, 1, n}, {j, 1, n}]
TableForm[m[8]] (* 8x8 principal submatrix *)
Flatten[Table[f[i, n + 1 - i],
  {n, 1, 14}, {i, 1, n}]]        (* A204431 *)
Permanent[m_] :=
  With[{a = Array[x, Length[m]]},
   Coefficient[Times @@ (m.a), Times @@ a]];
Table[Permanent[m[n]], {n, 1, 22}]  (* A204432 *)