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A012006
-arctanh(log(cos(x))) = 1/2!*x^2+2/4!*x^4+46/6!*x^6+1112/8!*x^8...
0
1, 2, 46, 1112, 63376, 4635872, 523749136, 76049858432, 14634264866176, 3496967323112192, 1032537134569578496, 366067157640456292352, 154146217678162805226496, 75874517780279404503590912
OFFSET
0,2
MATHEMATICA
Table[n!*SeriesCoefficient[-ArcTanh[Log[Cos[x]]], {x, 0, n}], {n, 2, 40, 2}] (* Vaclav Kotesovec, Oct 25 2013 *)
CROSSREFS
Sequence in context: A066555 A290046 A012001 * A279524 A264500 A173586
KEYWORD
nonn
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
STATUS
approved