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A012507
sec(cos(x)*arctan(x))=1+1/2!*x^2-15/4!*x^4+105/6!*x^6+8897/8!*x^8...
0
1, 1, -15, 105, 8897, -664815, -4523343, 8138992953, -972054629887, -115219461350367, 72803853486273265, -6666182957939643127, -7549270905441932464191, 4123382958180269131627825
OFFSET
0,3
CROSSREFS
Sequence in context: A165892 A349169 A077261 * A143727 A231327 A041426
KEYWORD
sign
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
STATUS
approved