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A012777 Expansion of e.g.f. arctanh(sec(x) * log(x+1)). 0
0, 1, -1, 7, -24, 223, -1635, 19409, -221592, 3270325, -50128965, 898512371, -17140184688, 364328185843, -8275583884295, 204221077642685, -5369189766162960, 151121003206989833, -4508710182336979593 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

Table of n, a(n) for n=0..18.

EXAMPLE

x - 1/2!*x^2 + 7/3!*x^3 - 24/4!*x^4 + 223/5!*x^5 ...

MATHEMATICA

Range[0, 20]! CoefficientList[ Series[ArcTanh[Sec[x] Log[x + 1]], {x, 0, 20}], x] (* Robert G. Wilson v, Jul 24 2018 *)

PROG

(PARI) x = 'x + O('x^30); concat(0, Vec(serlaplace(atanh(log(x+1)/cos(x))))) \\ Michel Marcus, Jul 27 2018

CROSSREFS

Sequence in context: A203117 A197791 A009652 * A074783 A286742 A322563

Adjacent sequences:  A012774 A012775 A012776 * A012778 A012779 A012780

KEYWORD

sign

AUTHOR

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

EXTENSIONS

a(0) inserted and title improved by Sean A. Irvine, Jul 24 2018

STATUS

approved

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Last modified October 14 14:45 EDT 2019. Contains 328019 sequences. (Running on oeis4.)