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A009644
Expansion of tan(log(1+x))*exp(x).
0
0, 1, 1, 4, -4, 55, -349, 3176, -31536, 356981, -4486515, 62124676, -939083124, 15387231899, -271629760609, 5139109612040, -103734448063424, 2225145262126601, -50544116286741191, 1212003840479789476
OFFSET
0,4
FORMULA
a(n) ~ n! * (-1)^(n+1) * exp(exp(-Pi/2)-1) / ((exp(Pi/2)-1) * (1-exp(-Pi/2))^n). - Vaclav Kotesovec, Jan 23 2015
MATHEMATICA
Tan[ Log[ 1+x ] ]*Exp[ x ]
CoefficientList[Series[E^x*Tan[Log[1 + x]], {x, 0, 20}], x] * Range[0, 20]! (* Vaclav Kotesovec, Jan 23 2015 *)
CROSSREFS
Sequence in context: A364763 A367891 A322099 * A196180 A369752 A156483
KEYWORD
sign,easy
AUTHOR
EXTENSIONS
Extended with signs by Olivier Gérard, Mar 15 1997
STATUS
approved