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A012003 E.g.f. cos(log(cos(x))), even powers only. 2
1, 0, -3, -30, -483, -12660, -492063, -26407290, -1854592743, -162954226920, -17150991170523, -2051454240374550, -254425037609483403, -24186909676571913180, 3098088521295623020617 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

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

FORMULA

For n>1, a(n) appears to be divisible by 3, and the highest exponent of 2 in a(2m+1) seems to be A001511(m). - Ralf Stephan, Aug 14 2013

MATHEMATICA

With[{nn=30}, Take[CoefficientList[Series[Cos[Log[Cos[x]]], {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Aug 29 2011 *)

CROSSREFS

Sequence in context: A218304 A242005 A276356 * A164945 A201466 A064352

Adjacent sequences:  A012000 A012001 A012002 * A012004 A012005 A012006

KEYWORD

sign

AUTHOR

Patrick Demichel (patrick.demichel(AT)hp.com)

STATUS

approved

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Last modified March 21 10:09 EDT 2019. Contains 321368 sequences. (Running on oeis4.)