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A278845 a(n) = permanent M_n where M_n is the n X n matrix m(i,j) = (i+j)^2.

%I A278845 #24 Aug 12 2021 08:45:45
%S A278845 1,4,145,19016,6176676,4038562000,4664347807268,8698721212922496,
%T A278845 24535712762777208384,99585504924929052560640,
%U A278845 559305193643176161735904320,4211594966980674975033969246720,41428564066728305721531962537124096,520897493876353116313789796095643304960
%N A278845 a(n) = permanent M_n where M_n is the n X n matrix m(i,j) = (i+j)^2.
%H A278845 Vaclav Kotesovec, <a href="/A278845/b278845.txt">Table of n, a(n) for n = 0..37</a>
%F A278845 a(n) ~ c * d^n * (n!)^3 / n, where d = 6.14071825... and c = 1.79385445... - _Vaclav Kotesovec_, Aug 12 2021
%p A278845 with(LinearAlgebra):
%p A278845 a:= n-> `if`(n=0, 1, Permanent(Matrix(n, (i, j)-> (i+j)^2))):
%p A278845 seq(a(n), n=0..16);  # _Vaclav Kotesovec_, Nov 29 2016, after _Alois P. Heinz_
%t A278845 Flatten[{1, Table[Permanent[Table[(i+j)^2, {i, 1, n}, {j, 1, n}]], {n, 1, 15}]}]
%o A278845 (PARI) {a(n) = matpermanent(matrix(n, n, i, j, (i+j)^2))}
%o A278845 for(n=0, 20, print1(a(n), ", ")) \\ _Vaclav Kotesovec_, Aug 09 2021
%Y A278845 Cf. A005249, A085750, A085807, A204249, A278847.
%K A278845 nonn
%O A278845 0,2
%A A278845 _Vaclav Kotesovec_, Nov 29 2016