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A204434 Permanent of the n-th principal submatrix of A204431. 3
0, 4, 9, 16, 192, 1032, 5184, 62496, 530712, 4188672, 61710336, 707802624, 7614259200, 133983590400, 1938416832000, 26579819520000, 544216485888000, 9509523337728000, 158654296829952000, 3711395156281344000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

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

MATHEMATICA

f[i_, j_] := Mod[2 i + 2 j + 2, 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}]]      (* A204433 *)

Permanent[m_] :=

  With[{a = Array[x, Length[m]]},

   Coefficient[Times @@ (m.a), Times @@ a]];

Table[Permanent[m[n]], {n, 1, 22}]    (* A204434 *)

CROSSREFS

Cf. A204233, A204263.

Sequence in context: A226354 A089149 A082920 * A110979 A073173 A253601

Adjacent sequences:  A204431 A204432 A204433 * A204435 A204436 A204437

KEYWORD

nonn

AUTHOR

Clark Kimberling, Jan 15 2012

STATUS

approved

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Last modified December 4 02:25 EST 2016. Contains 278745 sequences.