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A013202
Expansion of e.g.f. log(sech(x) + sin(x)).
0
0, 1, -2, 4, -12, 60, -392, 2784, -23072, 225680, -2475392, 29884864, -397554432, 5784292800, -91112993792, 1544557830144, -28059800686592, 543835022577920, -11198270349934592, 244140571254682624
OFFSET
0,3
EXAMPLE
x - 2/2!*x^2 + 4/3!*x^3 - 12/4!*x^4 + 60/5!*x^5 ...
CROSSREFS
Sequence in context: A058255 A118456 A326861 * A253832 A004400 A005831
KEYWORD
sign
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
EXTENSIONS
a(0)=0 inserted and title improved by Sean A. Irvine, Aug 01 2018
STATUS
approved