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A012768 exp(cosh(x)*arctan(x))=1+x+1/2!*x^2+2/3!*x^3+5/4!*x^4+20/5!*x^5... 0
1, 1, 1, 2, 5, 20, 85, 16, -887, 14096, 145865, -887456, -14963507, 126998976, 2554796829, -21834514688, -556819358703, 5067177011456, 157094249035537, -1485621376751104, -55286734778859115 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

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

MATHEMATICA

With[{nn=20}, CoefficientList[Series[Exp[Cosh[x]ArcTan[x]], {x, 0, nn}], x]Range[0, nn]!] (* Harvey P. Dale, Oct 07 2012 *)

CROSSREFS

Sequence in context: A286284 A286285 A192101 * A170947 A006228 A190656

Adjacent sequences:  A012765 A012766 A012767 * A012769 A012770 A012771

KEYWORD

sign

AUTHOR

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

STATUS

approved

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Last modified December 5 03:59 EST 2021. Contains 349530 sequences. (Running on oeis4.)