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A009376 Expansion of log(1 + tan(x)*exp(x)). 0
0, 1, 1, 1, -2, 5, 6, 131, -552, 3065, -10934, 216511, -1516052, 13359125, -110965074, 1704426491, -17363056752, 210045171185, -2585510594414, 41595973502071, -563643499480652, 8626434032607245, -136389526384050954 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,5
LINKS
FORMULA
a(n) ~ (n-1)! * (-1)^(n+1) / r^n, where r = 1.306326940423079236174356658440682315179068358... is the root of the equation tan(r)/exp(r) = 1. - Vaclav Kotesovec, Jan 24 2015
MATHEMATICA
Log[ 1+Tan[ x ]*Exp[ x ] ]
CoefficientList[Series[Log[1 + E^x*Tan[x]], {x, 0, 20}], x] * Range[0, 20]! (* Vaclav Kotesovec, Jan 24 2015 *)
CROSSREFS
Sequence in context: A111190 A244434 A176007 * A231364 A025123 A071791
KEYWORD
sign,easy
AUTHOR
EXTENSIONS
Extended with signs by Olivier Gérard, Mar 15 1997
STATUS
approved

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Last modified July 18 06:54 EDT 2024. Contains 374377 sequences. (Running on oeis4.)