A009429 E.g.f. log(1+x)/cos(x).

0, 1, -1, 5, -12, 69, -285, 2001, -12208, 104073, -854865, 8723549, -90552396, 1088372557, -13647385661, 190057979177, -2787246189120, 44285819490065, -742019231348865, 13267464006201781, -249642268776311020

Offset

0,4

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Formula

a(n) ~ (n-1)! * (-1)^(n+1) / cos(1). - Vaclav Kotesovec, Jan 23 2015

Example

log(1+x)/cos(x) = 0 + x - 1/2*x^2 + 5/6*x^3 - 1/2*x^4 + 23/40*x^5 -+ ...

Mathematica

With[{nn=30}, CoefficientList[Series[Log[1+x]/Cos[x], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Jan 26 2013 *)

Crossrefs

Sequence in context: A219770 A246176 A009413 * A207821 A297644 A242043

Adjacent sequences: A009426 A009427 A009428 * A009430 A009431 A009432

Keyword

sign,easy

Author

R. H. Hardin

Extensions

Extended with signs by Olivier Gérard, Mar 15 1997

Status

approved