A204426 Permanent of the n-th principal submatrix of A204425.

1, 1, 9, 34, 132, 1032, 6936, 51912, 530712, 5005152, 53529984, 707802624, 8714718720, 119716185600, 1938416832000, 29588291712000, 496487584512000, 9509523337728000, 173318541516288000, 3434389946233344000

Offset

1,3

Links

Table of n, a(n) for n=1..20.

Mathematica

f[i_, j_] := Mod[2 i + 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}]]       (* A204425 *)
Permanent[m_] :=
  With[{a = Array[x, Length[m]]},
   Coefficient[Times @@ (m.a), Times @@ a]];
Table[Permanent[m[n]], {n, 1, 22}]  (* A204426 *)

Crossrefs

Cf. A204225, A204263.

Sequence in context: A250763 A264678 A050478 * A154393 A119389 A197273

Adjacent sequences: A204423 A204424 A204425 * A204427 A204428 A204429

Keyword

nonn

Author

Clark Kimberling, Jan 15 2012

Status

approved