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A012565
sech(sinh(x)*arctan(x))=1-12/4!*x^4+120/6!*x^6+1680/8!*x^8...
0
1, 0, -12, 120, 1680, -4800, -20091456, 2552065152, -264925689600, 68708953577472, -29508519541947392, 12189637912025356288, -5505843502429896863744, 3137663619884947867484160
OFFSET
0,3
CROSSREFS
Sequence in context: A120585 A239188 A200163 * A012621 A102341 A174561
KEYWORD
sign
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
STATUS
approved