A204430 Permanent of the n-th principal submatrix of A204429.

1, 2, 9, 34, 144, 1032, 6936, 48816, 530712, 5005152, 50015232, 707802624, 8714718720, 112586112000, 1938416832000, 29588291712000, 469224244224000, 9509523337728000, 173318541516288000, 3261008730405888000

Offset

1,2

Links

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

Mathematica

f[i_, j_] := Mod[2 i + 2 j, 3];  (* symmetric *)
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}]]        (* A204429 *)
Permanent[m_] :=
  With[{a = Array[x, Length[m]]},
   Coefficient[Times @@ (m.a), Times @@ a]];
Table[Permanent[m[n]], {n, 1, 22}]   (* A204430 *)

Crossrefs

Cf. A204229, A204263.

Sequence in context: A091526 A274750 A204444 * A150937 A150938 A151307

Adjacent sequences: A204427 A204428 A204429 * A204431 A204432 A204433

Keyword

nonn

Author

Clark Kimberling, Jan 15 2012

Status

approved