# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a012752 Showing 1-1 of 1 %I A012752 #9 Oct 24 2013 16:22:08 %S A012752 1,2,16,398,18072,1465962,169054092,28688618814,6235376638608, %T A012752 1810793539845714,636329871517885332,282006422882452989030, %U A012752 145933818284739352119000,91644646853849910546846330 %N A012752 exp(arctanh(x)*arcsinh(x)) = 1+2/2!*x^2+16/4!*x^4+398/6!*x^6+18072/8!*x^8... %F A012752 a(n) ~ 2 * (2*n-1)! * (4*n)^(log(1+sqrt(2))/2) / GAMMA(log(1+sqrt(2))/2). - _Vaclav Kotesovec_, Oct 24 2013 %t A012752 Table[n!*SeriesCoefficient[Exp[ArcTanh[x]*ArcSinh[x]],{x,0,n}],{n,0,40,2}] (* _Vaclav Kotesovec_, Oct 24 2013 *) %K A012752 nonn %O A012752 0,2 %A A012752 Patrick Demichel (patrick.demichel(AT)hp.com) # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE