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A013505
arcsin(sec(x)-sech(x))=2/2!*x^2+242/6!*x^6+680642/10!*x^10...
0
2, 242, 680642, 12295286642, 793097630442242, 133559779986589891442, 48615807873566074448898242, 33724812804150581105792438246642, 40740665803925610662412399036224240642, 80080558510702094594473104537545729044704242, 242897198718040825682993782394774029906856140981442
OFFSET
0,1
CROSSREFS
Sequence in context: A309037 A013509 A013472 * A013478 A049333 A140162
KEYWORD
nonn
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
EXTENSIONS
More terms from N. J. A. Sloane, Dec 17 2011
STATUS
approved