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%I #17 Feb 20 2023 13:06:24
%S 0,1,-1,5,-22,151,-1186,11255,-121752,1493101,-20381896,306816905,
%T -5045231632,89977880851,-1729461315856,35637607318955,
%U -783658693590912,18315607922069401,-453368586519154816,11848112075773043405
%N Expansion of e.g.f.: tan(log(1+sinh(x))).
%F a(n) ~ n! * (-1)^(n+1) / (sqrt(1-2*exp(Pi/2)+2*exp(Pi)) * log(1 - exp(-Pi/2) + sqrt(1 + (exp(-Pi/2)-1)^2))^(n+1)). - _Vaclav Kotesovec_, Jan 23 2015
%t CoefficientList[Series[Tan[Log[1 + Sinh[x]]], {x, 0, 20}], x] * Range[0, 20]! (* _Vaclav Kotesovec_, Jan 23 2015 *)
%K sign,easy
%O 0,4
%A _R. H. Hardin_
%E Extended with signs by _Olivier Gérard_, Mar 15 1997
%E First Mathematica program deleted and definition clarified by _Harvey P. Dale_, Feb 20 2023