OFFSET
0,2
COMMENTS
Row n of triangle T=A134090 = row n of (I + D*C)^n for n>=0 where C denotes Pascal's triangle, I the identity matrix and D a matrix where D(n+1,n)=1 and zeros elsewhere.
FORMULA
a(n) = [x^n] Sum_{k=0..n+3} C(n+3,k)*x^k/(1-k*x)^3 / [Product_{i=1..k}(1-i*x)].
PROG
(PARI) {a(n)= polcoeff(sum(k=0, n+3, binomial(n+3, k)*x^k/(1-k*x)^3/prod(i=0, k, 1-i*x +x*O(x^n))), n)}
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Oct 08 2007
STATUS
approved