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A009080 Expansion of cos(x*tan(x)). 1
1, 0, -12, -240, -5936, -155520, -65472, 981903104, 223580862720, 46255608778752, 10060678641587200, 2368138744630923264, 601490101481648443392, 161192778898870464512000, 43208403753541588946141184 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..14.

EXAMPLE

cos(x*tan(x)) = 1/0! +0*x^2/2! -12*x^4/4! -240*x^6/6! -5936*x^8/8! -...

MATHEMATICA

Cos[ Tan[ x ]*x ] (* Even Part *)

CROSSREFS

Sequence in context: A012538 A006588 A009150 * A002166 A034910 A091745

Adjacent sequences:  A009077 A009078 A009079 * A009081 A009082 A009083

KEYWORD

sign

AUTHOR

R. H. Hardin

EXTENSIONS

Extended with signs by Olivier Gérard, Mar 15 1997

STATUS

approved

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Last modified February 24 11:06 EST 2018. Contains 299603 sequences. (Running on oeis4.)