OFFSET
0,2
COMMENTS
The g.f. of triangle A181144 is exp( Sum_{n>=1} [Sum_{k=0..n} C(n,k)^4*y^k] * x^n/n ).
PROG
(PARI) {a(n)=polcoeff(polcoeff(exp(sum(m=1, 2*n, sum(j=0, m, binomial(m, j)^4*y^j)*x^m/m)+O(x^(2*n+1))), 2*n, x), n, y)}
for(n=0, 20, print1(a(n), ", "))
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Oct 21 2012
STATUS
approved