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A012930 arcsinh(tan(x)+log(x+1)) = 2*x-1/2!*x^2-4/3!*x^3+18/4!*x^4+138/5!*x^5... 0
0, 2, -1, -4, 18, 138, -1425, -7368, 207340, 481578, -49899645, 122677012, 17081066310, -160273109518, -7677995678717, 153514412519392, 4141750812789720, -158348457721397742, -2343499454063177433 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

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

FORMULA

Lim sup n->infinity (|a(n)|/n!)^(1/n) = 1.88681124646597... = abs(1/r), where r is the complex root of the equation log(r+1)*cos(r)*(2*sin(r) + log(r+1)*cos(r)) = -1. - Vaclav Kotesovec, Nov 02 2013

MATHEMATICA

CoefficientList[Series[ArcSinh[Tan[x]+Log[x+1]], {x, 0, 20}], x]* Range[0, 20]! (* Vaclav Kotesovec, Nov 01 2013 *)

CROSSREFS

Sequence in context: A192494 A013156 A012925 * A013162 A010252 A032105

Adjacent sequences:  A012927 A012928 A012929 * A012931 A012932 A012933

KEYWORD

sign

AUTHOR

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

EXTENSIONS

Prepended missing a(0)=0 from Vaclav Kotesovec, Nov 01 2013

STATUS

approved

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Last modified August 12 19:14 EDT 2022. Contains 356077 sequences. (Running on oeis4.)