A013028 tan(sinh(x)+sin(x))=2*x+16/3!*x^3+514/5!*x^5+35152/7!*x^7...

2, 16, 514, 35152, 4127746, 740674064, 188488949250, 64571541708368, 28651429011593218, 15984853455121457680, 10952019804412753091074, 9040261830823734670831952, 8848477099508752781113283586

Offset

0,1

Links

Vaclav Kotesovec, Table of n, a(n) for n = 0..200

Vaclav Kotesovec, Graph - abs(e.g.f.) in the complex plane

Formula

a(n) ~ 2 * (2*n+1)! / ((cos(r) + cosh(r)) * r^(2*n+2)), where r = 0.782946098053298645157328067127669055159808275911641432279... is the root of the equation sinh(r) + sin(r) = Pi/2. - Vaclav Kotesovec, Feb 07 2015

Mathematica

nn = 20; Table[(CoefficientList[Series[Tan[Sin[x] + Sinh[x]], {x, 0, 2*nn+1}], x] * Range[0, 2*nn+1]!)[[n]], {n, 2, 2*nn, 2}] (* Vaclav Kotesovec, Feb 07 2015 *)

Crossrefs

Sequence in context: A286039 A063391 A002416 * A136632 A168405 A012919

Adjacent sequences: A013025 A013026 A013027 * A013029 A013030 A013031

Keyword

nonn

Author

Patrick Demichel (patrick.demichel(AT)hp.com)

Status

approved