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Permanent of the n-th principal submatrix of A204551.
2

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

%S 1,2,8,75,1157,23974,655636,24625600,1208111716,71223596496,

%T 5012804515680,428588572904208,43766538817494528,5110290596191238784,

%U 679891748332818756096

%N Permanent of the n-th principal submatrix of A204551.

%t f[i_, j_] :=

%t Floor[(2 i + 2 j + 1)/4] - Floor[(i + j)/4];

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

%t TableForm[m[16]] (* 8x8 principal submatrix *)

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

%t {n, 1, 14}, {i, 1, n}]] (* A204551 *)

%t Permanent[m_] :=

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

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

%t Table[Permanent[m[n]], {n, 1, 15}] (* A204552 *)

%Y Cf. A204551.

%K nonn

%O 1,2

%A _Clark Kimberling_, Jan 16 2012