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Permanent of the n-th principal submatrix of A204445.
3

%I #6 Jul 12 2012 00:39:59

%S 1,1,3,9,34,116,792,4752,32304,202320,1991952,17927568,175473216,

%T 1613364480,20695108608,248341303296,3173837230080,38575603814400,

%U 610011772416000,9150176586240000,144343174487040000,2183607168215040000

%N Permanent of the n-th principal submatrix of A204445.

%t f[i_, j_] :=

%t Floor[(i + j + 4)/4] - Floor[(i + j + 1)/4];

%t m[n_] := Table[f[i, j], {i, 1, n}, {j, 1, n}]

%t TableForm[m[8]] (* 8x8 principal submatrix *)

%t Flatten[Table[f[i, n + 1 - i],

%t {n, 1, 14}, {i, 1, n}]] (* A204445 *)

%t Permanent[m_] :=

%t With[{a = Array[x, Length[m]]},

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

%t Table[Permanent[m[n]], {n, 1, 22}] (* A204446 *)

%Y Cf. A204245, A204435.

%K nonn

%O 1,3

%A _Clark Kimberling_, Jan 15 2012