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A012841 sin(sec(x)*arctanh(x))=x+4/3!*x^3+20/5!*x^5-1024/7!*x^7-147568/9!*x^9... 0
1, 4, 20, -1024, -147568, -19148736, -2934842560, -551525234688, -127249126657792, -35789287036394496, -12158191126869847040, -4941201795126314303488, -2379230211581147229286400 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..12.

CROSSREFS

Sequence in context: A160703 A132511 A144989 * A074195 A332867 A217369

Adjacent sequences:  A012838 A012839 A012840 * A012842 A012843 A012844

KEYWORD

sign

AUTHOR

Patrick Demichel (patrick.demichel(AT)hp.com)

STATUS

approved

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Last modified December 3 21:17 EST 2021. Contains 349468 sequences. (Running on oeis4.)