A204254 Permanent of the n-th principal submatrix of A204253.

3, 7, 54, 466, 3732, 50928, 748224, 10421856, 204446592, 4232598624, 84204904320, 2154137877504, 57534363970560, 1488803964595200, 46983956781312000, 1536963329488896000, 48976637440702464000, 1838658764187353088000

Offset

1,1

Links

Table of n, a(n) for n=1..18.

Mathematica

f[i_, j_] := 1 + Mod[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, 12}, {i, 1, n}]]  (* A204253  *)
Permanent[m_] :=
  With[{a = Array[x, Length[m]]},
   Coefficient[Times @@ (m.a), Times @@ a]];
Table[Permanent[m[n]], {n, 1, 20}] (* A204254  *)

Crossrefs

Cf. A204253.

Sequence in context: A058023 A285065 A095124 * A144030 A228490 A130294

Adjacent sequences: A204251 A204252 A204253 * A204255 A204256 A204257

Keyword

nonn

Author

Clark Kimberling, Jan 14 2012

Status

approved