OFFSET
0,2
COMMENTS
Compare to an e.g.f. of A122399: Sum_{n>=0} exp(n^2*x)/(1 + exp(n*x))^(n+1).
EXAMPLE
E.g.f.: A(x) = 1 - 4*x^2/2! + 1172*x^4/4! - 2394604*x^6/6! + 17925470132*x^8/8! -+...
where
A(x) = 1/2 + exp(x)/(1+exp(x))^2 + exp(3*x)/(1+exp(2*x))^3 + exp(6*x)/(1+exp(3*x))^4 + exp(10*x)/(1+exp(4*x))^5 + exp(15*x)/(1+exp(5*x))^6 + exp(21*x)/(1+exp(6*x))^7 +...
PROG
(PARI) \p100 \\ set precision
{A=Vec(serlaplace(sum(n=0, 800, 1.*exp((n^2+n)/2*x +O(x^31))/(1 + exp(n*x +O(x^31)))^(n+1)) ))}
for(n=1, #A\2, print1(round(A[2*n-1]), ", "))
CROSSREFS
KEYWORD
sign
AUTHOR
Paul D. Hanna, Oct 26 2014
STATUS
approved