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A012840
exp(sec(x)*arctanh(x))=1+x+1/2!*x^2+6/3!*x^3+21/4!*x^4+120/5!*x^5...
1
1, 1, 1, 6, 21, 120, 765, 5376, 46473, 415104, 4371225, 48143744, 594635613, 7784817664, 110691178325, 1673986906112, 27018807872657, 462531126525952, 8370279766396593, 159859054841331712
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OFFSET
0,4
LINKS
Table of n, a(n) for n=0..19.
CROSSREFS
Sequence in context:
A009253
A365880
A251593
*
A013320
A056308
A081077
Adjacent sequences:
A012837
A012838
A012839
*
A012841
A012842
A012843
KEYWORD
nonn
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
STATUS
approved
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Last modified May 18 07:16 EDT 2024. Contains 372618 sequences. (Running on oeis4.)