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%I #5 Apr 05 2016 08:25:20
%S -1,0,675,11309768,878801253135,208241673295152024,
%T 118270071682117442287235,137788343929239264227213170608,
%U 295355309179742652677310128859789375
%N a(n) = Sinh[(2n-1)ArcCosh[n]]^2.
%F a(n) ~ 2^(4*n-4) * n^(4*n-2). - _Vaclav Kotesovec_, Apr 05 2016
%t Table[Round[Sinh[(2 n - 1) ArcCosh[n]]^2], {n, 0, 20}]
%Y Cf. A058331, A001079, A037270, A071253, A108741, A132592, A146311, A146312, A146313, A173115, A173116, A173121, A173127, A173128, A173129, A173130, A173131, A173133.
%K sign
%O 0,3
%A _Artur Jasinski_, Feb 10 2010