A204422 Permanent of the n-th principal submatrix of A204269.

1, 1, 1, 2, 6, 20, 48, 288, 1344, 6624, 28512, 212544, 1425600, 10056960, 61378560, 600514560, 5185658880, 46664294400, 374492160000, 4406814720000, 46820229120000, 515545067520000, 5128069201920000, 70905056624640000, 893661057515520000, 11621453908377600000

Offset

1,4

Links

G. C. Greubel, Table of n, a(n) for n = 1..100

Mathematica

f[i_, j_] := Floor[(i + j + 2)/4] - Floor[(i + j)/4];
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}]]    (* A204269 *)
Permanent[m_] :=
  With[{a = Array[x, Length[m]]}, Coefficient[Times @@ (m.a), Times @@ a]];
Table[Permanent[m[n]], {n, 1, 22}]    (* A204422 *)

Crossrefs

Cf. A204269.

Sequence in context: A193538 A121128 A056820 * A027558 A320910 A066397

Adjacent sequences: A204419 A204420 A204421 * A204423 A204424 A204425

Keyword

nonn

Author

Clark Kimberling, Jan 16 2012

Status

approved