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A204266 Permanent of the n-th principal submatrix of A204123. 1

%I

%S 1,5,27,252,2369,36103,518000,9756177,200951191,4899768134,

%T 113249415026,3553351288210,105127854228522,3433390910771142,

%U 122658122808278570,4957371400718135098,191264018429152335168

%N Permanent of the n-th principal submatrix of A204123.

%t f[i_, j_] := Floor[Max[i, j]/Min[i, j]];

%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, 12}, {i, 1, n}]] (* A204123 *)

%t Permanent[m_] :=

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

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

%t Table[Permanent[m[n]], {n, 1, 14}] (* A204266 *)

%Y Cf. A204123.

%K nonn

%O 1,2

%A _Clark Kimberling_, Jan 14 2012

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Last modified January 17 17:33 EST 2021. Contains 340247 sequences. (Running on oeis4.)