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%I #6 Jul 12 2012 00:39:59
%S 1,2,13,104,1357,22052,555325,17622590,680239111,31511481788,
%T 1717710101869,109014509616567,8596454332733239,783330147715515842,
%U 79369033657791374935,9105430313767018411610
%N Permanent of the n-th principal submatrix of A204260.
%t f[i_, j_] := Ceiling[i*j/(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}]] (* A204260 *)
%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}] (* A204261 *)
%Y Cf. A204260.
%K nonn
%O 1,2
%A _Clark Kimberling_, Jan 14 2012