%I #6 Oct 15 2016 11:10:46
%S 1,2,5,34,569,14426,518557,25400810,1625695409,131681938834,
%T 13168189962101,1593350918236562,229442532743676265,
%U 38775788044161003434,7600054456561351409549,1710012252724103327072026,437763136697393060993682017,126513546505547193228474910370
%N a(n) = |Gamma(n, i)|^2, where i = sqrt(-1).
%H Eric Weisstein's MathWorld, <a href="http://mathworld.wolfram.com/IncompleteGammaFunction.html">Incomplete Gamma Function</a>
%F a(n) = |Gamma(n, i)|^2 = Gamma(n, i)*Gamma(n, -i), where i = sqrt(-1).
%F a(n) = A009102(n-1)^2 + A009551(n-1)^2.
%F Recurrence: n*(n-1)*(a(n-1) - (n-2)^2*a(n-2) + 1) + a(n+1) = n^2*a(n) + 1.
%F a(n) ~ (n-1)!^2. - _Vaclav Kotesovec_, Oct 15 2016
%t RecurrenceTable[{n (n - 1) (a[n - 1] - (n - 2)^2 a[n - 2] + 1) + a[n + 1] == n^2 a[n] + 1, a[1] == 1, a[2] == 2, a[3] == 5}, a[n], {n, 1, 20}] (* or *)
%t Round[Abs[Gamma[Range[20], I]]^2]
%Y Cf. A009102, A009551.
%K nonn
%O 1,2
%A _Vladimir Reshetnikov_, Oct 14 2016
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