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A278925 a(n) = permanent M_n where M_n is the n X n matrix m(i,j) = i^3 + j^3.

%I A278925 #12 Dec 23 2018 16:39:43
%S A278925 1,2,113,38736,46311652,143820883800,966462062838180,
%T A278925 12412328008727861760,278484670746890475310656,
%U A278925 10197331743850942940587152000,577793817845799602600135280168000,48534819511412868687827815575204633600,5834998526939444017550860154062183732711680
%N A278925 a(n) = permanent M_n where M_n is the n X n matrix m(i,j) = i^3 + j^3.
%H A278925 Vaclav Kotesovec, <a href="/A278925/b278925.txt">Table of n, a(n) for n = 0..36</a>
%F A278925 a(n) ~ c * d^n * n!^4 / n^(3/2), where d = 6.538385468679... and c = 0.84959670006...
%p A278925 with(LinearAlgebra):
%p A278925 a:= n-> `if`(n=0, 1, Permanent(Matrix(n, (i, j)-> i^3+j^3))):
%p A278925 seq(a(n), n=0..16);
%t A278925 Flatten[{1, Table[Permanent[Table[i^3+j^3, {i, 1, n}, {j, 1, n}]], {n, 1, 15}]}]
%o A278925 (PARI) {a(n) = matpermanent(matrix(n, n, i, j, i^3+j^3))}
%o A278925 for(n=0, 20, print1(a(n), ", ")) \\ _Vaclav Kotesovec_, Dec 21 2018
%Y A278925 Cf. A204249, A278847, A278926.
%K A278925 nonn
%O A278925 0,2
%A A278925 _Vaclav Kotesovec_, Dec 01 2016