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Obverse convolution (n^2)**(n^2+1); see Comments.
1

%I #8 Sep 14 2024 16:47:25

%S 1,4,75,3600,314721,42928704,8362250379,2196324000000,746766466070625,

%T 318799285706474496,166848786507705952491,105015062916733187395584,

%U 78238953853457166762890625,68086982534559349084416000000,68431651668664224198422729187051

%N Obverse convolution (n^2)**(n^2+1); see Comments.

%C See A374848 for the definition of obverse convolution and a guide to related sequences.

%F a(n) ~ exp((Pi-4)*n/2) * n^(2*n+2). - _Vaclav Kotesovec_, Sep 13 2024

%t s[n_] := n^2; t[n_] := n^2 + 1;

%t u[n_] := Product[s[k] + t[n - k], {k, 0, n}]

%t Table[u[n], {n, 0, 20}]

%Y Cf. A000290, A002522, A374848.

%K nonn

%O 0,2

%A _Clark Kimberling_, Sep 13 2024