A204424 Permanent of the n-th principal submatrix of A204423.

0, 2, 9, 16, 144, 1032, 5184, 48816, 530712, 4188672, 50015232, 707802624, 7614259200, 112586112000, 1938416832000, 26579819520000, 469224244224000, 9509523337728000, 158654296829952000, 3261008730405888000

Offset

1,2

Links

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

Mathematica

f[i_, j_] := Mod[2 i + j, 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}]]      (* A204423 *)
Permanent[m_] :=
  With[{a = Array[x, Length[m]]},
   Coefficient[Times @@ (m.a), Times @@ a]];
Table[Permanent[m[n]], {n, 1, 22}]  (* A204424 *)

Crossrefs

Cf. A204223, A204263.

Sequence in context: A369647 A078707 A085332 * A062981 A069622 A334193

Adjacent sequences: A204421 A204422 A204423 * A204425 A204426 A204427

Keyword

nonn

Author

Clark Kimberling, Jan 15 2012

Status

approved