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A013339
sech(exp(x)-sec(x))=1-1/2!*x^2+1/4!*x^4+20/5!*x^5+23/6!*x^6...
0
1, 0, -1, 0, 1, 20, 23, -140, -975, -1656, 74751, 365640, 1284369, -26269412, -120532297, 1518753340, 37230940193, 312855107472, -1646816770497, -37424409392880, -167334452580383, 9798194248744356
OFFSET
0,6
CROSSREFS
Sequence in context: A358424 A303303 A045563 * A199360 A199585 A093716
KEYWORD
sign
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
STATUS
approved