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A009369 Expansion of log(1+tan(x))*cos(x). 0
0, 1, -1, 1, -8, 45, -301, 2357, -21608, 223769, -2602081, 33484713, -473210528, 7282225093, -121272163741, 2172791685469, -41680241726768, 852337358029617, -18510436676621281, 425474580069715025, -10319766893265298328 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,5
LINKS
FORMULA
a(n) ~ (n-1)! * (-1)^(n+1) * 2^(2*n-1/2) / Pi^n. - Vaclav Kotesovec, Jan 23 2015
MATHEMATICA
Log[ 1+Tan[ x ] ]*Cos[ x ]
CoefficientList[Series[Cos[x]*Log[1 + Tan[x]], {x, 0, 20}], x] * Range[0, 20]! (* Vaclav Kotesovec, Jan 23 2015 *)
CROSSREFS
Sequence in context: A289896 A367435 A006887 * A120044 A328885 A002686
KEYWORD
sign,easy
AUTHOR
EXTENSIONS
Extended with signs by Olivier Gérard, Mar 15 1997
STATUS
approved

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Last modified April 27 12:38 EDT 2024. Contains 372019 sequences. (Running on oeis4.)