A013194 Expansion of e.g.f. log(sec(x) + sin(x)).

0, 1, 0, -2, 12, -40, 120, 208, -6048, 64640, -428160, 986368, 29812992, -652487680, 8332047360, -60911593472, -293043130368, 20973645824000, -456591699640320, 6185783347314688, -26996975653552128

Offset

0,4

Links

Table of n, a(n) for n=0..20.

Formula

E.g.f.: log(sec(x) + sin(x)).

Example

x - 2/3!*x^3 + 12/4!*x^4 - 40/5!*x^5 + 120/6!*x^6 ...

Crossrefs

Sequence in context: A143126 A118417 A069144 * A212874 A074447 A190064

Adjacent sequences: A013191 A013192 A013193 * A013195 A013196 A013197

Keyword

sign

Author

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

Extensions

a(0)=0 inserted and title improved by Sean A. Irvine, Aug 01 2018

Status

approved