OFFSET
0,2
FORMULA
a(0) = 1; a(n) = -4 * (n-1)! * Sum_{k=1..min(4,n)} binomial(3,k-1) * a(n-k)/(n-k)!.
a(n) = Sum_{k=0..n} 4^k * Stirling1(n,k) * A000587(k).
D-finite with recurrence a(n) +4*a(n-1) +12*(n-1)*a(n-2) +12*(n-1)*(n-2)*a(n-3) +4*(n-1)*(n-2)*(n-3)*a(n-4)=0. - R. J. Mathar, Feb 02 2024
MATHEMATICA
With[{nn=20}, CoefficientList[Series[Exp[1-(1+x)^4], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Mar 29 2024 *)
PROG
(PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(exp(1-(1+x)^4)))
CROSSREFS
KEYWORD
sign
AUTHOR
Seiichi Manyama, Jan 30 2024
STATUS
approved