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%I #6 Mar 19 2016 16:17:11
%S 1,0,1,6,21,100,1005,9170,73353,794952,11042745,144625118,1936131549,
%T 31475441452,562265168101,9960214270890,187956163443857,
%U 3970728871687824,88040662078595313,1994667867977462454
%N Expansion of e.g.f.: sec(arctan(x)*exp(x))=1+1/2!*x^2+6/3!*x^3+21/4!*x^4+100/5!*x^5...
%t With[{nn=20},CoefficientList[Series[Sec[ArcTan[x]Exp[x]],{x,0,nn}],x] Range[0,nn]!] (* _Harvey P. Dale_, Mar 19 2016 *)
%K nonn
%O 0,4
%A Patrick Demichel (patrick.demichel(AT)hp.com)
%E Definition clarified by _Harvey P. Dale_, Mar 19 2016