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A012836
arcsinh(sec(x)*tanh(x))=x+20/5!*x^5-280/7!*x^7+18000/9!*x^9...
0
1, 0, 20, -280, 18000, -1277760, 159922880, -26119949440, 5923118588160, -1705199348152320, 619341836139299840, -274598298613483878400, 146431095418622106193920, -92305017354779154307399680
OFFSET
0,3
CROSSREFS
Sequence in context: A021474 A017999 A244653 * A028294 A278360 A019040
KEYWORD
sign
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
STATUS
approved