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A009363 Expansion of log(1+tan(log(1+x))). 0
0, 1, -2, 9, -55, 434, -4180, 47590, -625770, 9339880, -156097760, 2889491800, -58706203400, 1299203207600, -31115627649600, 801958361812400, -22134642846706000, 651438145653776000, -20365743882600064000 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

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

FORMULA

a(n) ~ (n-1)! * (-1)^(n+1) / (1-exp(-Pi/4))^n. - Vaclav Kotesovec, Jan 23 2015

MATHEMATICA

With[{nn=20}, CoefficientList[Series[Log[1+Tan[Log[1+x]]], {x, 0, nn}], x]Range[0, nn]!] (* Harvey P. Dale, Sep 28 2011 *)

CROSSREFS

Sequence in context: A078455 A036074 A231172 * A069564 A109366 A241457

Adjacent sequences:  A009360 A009361 A009362 * A009364 A009365 A009366

KEYWORD

sign,easy

AUTHOR

R. H. Hardin

EXTENSIONS

Extended with signs by Olivier Gérard, Mar 15 1997

STATUS

approved

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Last modified December 3 10:49 EST 2016. Contains 278699 sequences.