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A009416
Expansion of e.g.f. log(1+x)*cosh(x).
4
0, 1, -1, 5, -12, 49, -225, 1301, -8848, 69441, -616185, 6095429, -66475596, 792143793, -10238194057, 142633278997, -2130537219840, 33964965659649, -575573407212753, 10331348137881349, -195807849389362540, 3907452790559751857, -81892400673047263761, 1798373345567005989781, -41294565798306731368272, 989581607891834678407745
OFFSET
0,4
FORMULA
a(n) ~ (n-1)! * (-1)^(n+1) * cosh(1). - Vaclav Kotesovec, Jan 23 2015
a(n) = -(-1)^n * Sum_{k=0..floor((n-1)/2)} binomial(n,2*k) * (n-2*k-1)!. - Ilya Gutkovskiy, Apr 10 2022
MATHEMATICA
CoefficientList[Series[Cosh[x]*Log[1 + x], {x, 0, 20}], x] * Range[0, 20]! (* Vaclav Kotesovec, Jan 23 2015 *)
CROSSREFS
Cf. A009410.
Sequence in context: A211951 A356539 A009425 * A332477 A240389 A135769
KEYWORD
sign,easy
AUTHOR
EXTENSIONS
Extended with signs by Olivier Gérard, Mar 15 1997
STATUS
approved