A012771 exp(cosh(x)*arcsinh(x))=1+x+1/2!*x^2+3/3!*x^3+9/4!*x^4+25/5!*x^5...

1, 1, 1, 3, 9, 25, 105, 371, 1393, 11985, 71025, -13981, -898887, 45127017, 455252889, -5553908333, -75822681503, 1415759895841, 21366754787169, -404022487469117, -7036035942040855, 148035510590478137

Offset

0,4

Links

Table of n, a(n) for n=0..21.

Formula

E.g.f.: (x+sqrt(1+x^2))^(cosh(x)). - Vaclav Kotesovec, Nov 01 2013

a(n) ~ 2*cos(1) * sin(Pi/2*(n-cos(1))) * n^(n-1) / exp(n). - Vaclav Kotesovec, Nov 01 2013

Mathematica

CoefficientList[Series[Exp[Cosh[x]*ArcSinh[x]], {x, 0, 20}], x]* Range[0, 20]! (* Vaclav Kotesovec, Nov 01 2013 *)

Crossrefs

Sequence in context: A192371 A363467 A192465 * A351891 A178061 A120284

Adjacent sequences: A012768 A012769 A012770 * A012772 A012773 A012774

Keyword

sign

Author

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

Status

approved