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A204448 Permanent of the n-th principal submatrix of A204447.

%I A204448 #6 Jul 12 2012 00:39:59
%S A204448 0,1,3,9,24,140,792,4752,27072,230832,1991952,17927568,155644416,
%T A204448 1780206336,20695108608,248341303296,2898196070400,41713375334400,
%U A204448 610011772416000,9150176586240000,134163172454400000,2329812142295040000
%N A204448 Permanent of the n-th principal submatrix of A204447.
%t A204448 f[i_, j_] :=
%t A204448  Floor[(i + j + 5)/4] - Floor[(i + j + 2)/4];
%t A204448 m[n_] := Table[f[i, j], {i, 1, n}, {j, 1, n}]
%t A204448 TableForm[m[8]] (* 8x8 principal submatrix *)
%t A204448 Flatten[Table[f[i, n + 1 - i],
%t A204448   {n, 1, 14}, {i, 1, n}]]     (* A204447 *)
%t A204448 Permanent[m_] :=
%t A204448   With[{a = Array[x, Length[m]]},
%t A204448    Coefficient[Times @@ (m.a), Times @@ a]];
%t A204448 Table[Permanent[m[n]], {n, 1, 22}]    (* A204448 *)
%Y A204448 Cf. A204247, A204435.
%K A204448 nonn
%O A204448 1,3
%A A204448 _Clark Kimberling_, Jan 15 2012