%I #12 Nov 01 2013 14:08:56
%S 1,4,24,534,16520,1017914,66612612,8612481206,839464647792,
%T 223263066398386,20349154329810172,15355587487339427086,
%U -408311328299061735320,2681720930486026740373066,-832148640269649203971185996,1101363338244005265784426750566
%N cosh(arcsinh(x)+tan(x))=1+4/2!*x^2+24/4!*x^4+534/6!*x^6+16520/8!*x^8...
%F a(n) ~ (-1)^(n+1) * 2^(2*n) * n^(2*n-1) * cos(tanh(1)) / exp(2*n). - _Vaclav Kotesovec_, Nov 01 2013
%t With[{nn=40},Take[CoefficientList[Series[Cosh[ArcSinh[x]+Tan[x]],{x,0,nn}],x] Range[0,nn]!,{1,-1,2}]] (* _Harvey P. Dale_, Feb 23 2013 *)
%K sign
%O 0,2
%A Patrick Demichel (patrick.demichel(AT)hp.com)
%E Checked by _N. J. A. Sloane_, Dec 17 2011
%E More terms from _Harvey P. Dale_, Feb 23 2013
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