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A009139
Expansion of e.g.f. cosh(log(1+x)/exp(x)).
1
1, 0, 1, -9, 60, -390, 2820, -24010, 238336, -2659104, 32417160, -426027008, 6004088112, -90491148176, 1454386367616, -24843370627920, 449435283828992, -8582294948325760, 172476215457600000, -3638420414864043264
OFFSET
0,4
LINKS
FORMULA
a(n) ~ (-1)^n * n! * n^(exp(1) - 1) / (2 * Gamma(exp(1))). - Vaclav Kotesovec, Jul 31 2018
MAPLE
seq(coeff(series(factorial(n)*cosh(log(1+x)/exp(x)), x, n+1), x, n), n=0..20); # Muniru A Asiru, Jul 31 2018
MATHEMATICA
With[{nmax = 30}, CoefficientList[Series[Cosh[Log[1 + x]/Exp[x]], {x, 0, nmax}], x]*Range[0, nmax]!] (* G. C. Greubel, Jul 30 2018 *)
PROG
(PARI) x='x+O('x^30); Vec(serlaplace(cosh(log(1+x)/exp(x)))) \\ G. C. Greubel, Jul 30 2018
(Magma) m:=30; R<x>:=PowerSeriesRing(Rationals(), m); b:=Coefficients(R!(Cosh(Log(1+x)/Exp(x)))); [Factorial(n-1)*b[n]: n in [1..m]]; // G. C. Greubel, Jul 30 2018
CROSSREFS
Sequence in context: A082150 A026785 A153820 * A086018 A197402 A213133
KEYWORD
sign,easy
AUTHOR
EXTENSIONS
Extended with signs by Olivier Gérard, Mar 15 1997
STATUS
approved