A009220 Sum(a(n)*x^n/n!) = exp(sinh(sinh(x))).

1, 1, 1, 3, 9, 33, 153, 731, 4273, 25857, 177489, 1311379, 10342137, 89060065, 800697641, 7778778091, 78896218081, 849264442881, 9587206592289, 113234181108643, 1403875965476969, 18073465545032353, 243412313149166137, 3395124358886313595, 49273184499900888465

Offset

0,4

Links

Table of n, a(n) for n=0..24.

Formula

E.g.f.: exp(sinh(sinh(x))).

Mathematica

Exp[ Sinh[ Sinh[ x ] ] ]

Prog

(PARI) vector(#t=Vec(exp(sinh(sinh(x)))), n, t[n]*(n-1)!)  \\ M. F. Hasler, Jan 12 2013

Crossrefs

Sequence in context: A101899 A180632 A279840 * A294035 A007489 A294638

Adjacent sequences: A009217 A009218 A009219 * A009221 A009222 A009223

Keyword

nonn,easy

Author

R. H. Hardin

Extensions

Extended and signs checked by Olivier Gérard, Mar 15 1997.

Better definition by M. F. Hasler, Jan 12 2013

Status

approved