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A012752
exp(arctanh(x)*arcsinh(x)) = 1+2/2!*x^2+16/4!*x^4+398/6!*x^6+18072/8!*x^8...
1
1, 2, 16, 398, 18072, 1465962, 169054092, 28688618814, 6235376638608, 1810793539845714, 636329871517885332, 282006422882452989030, 145933818284739352119000, 91644646853849910546846330
OFFSET
0,2
FORMULA
a(n) ~ 2 * (2*n-1)! * (4*n)^(log(1+sqrt(2))/2) / GAMMA(log(1+sqrt(2))/2). - Vaclav Kotesovec, Oct 24 2013
MATHEMATICA
Table[n!*SeriesCoefficient[Exp[ArcTanh[x]*ArcSinh[x]], {x, 0, n}], {n, 0, 40, 2}] (* Vaclav Kotesovec, Oct 24 2013 *)
CROSSREFS
Sequence in context: A009613 A012388 A297368 * A188904 A189104 A347914
KEYWORD
nonn
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
STATUS
approved