A125809 Row sums of triangle A125806.

1, 2, 4, 8, 18, 44, 120, 348, 1064, 3368, 10952, 36336, 122570, 419104, 1449672, 5064240, 17844558, 63356072, 226459120, 814323856, 2944055592, 10695723368, 39029679176, 142998497292, 525862368660, 1940381764088, 7182278240848

Offset: 0

Author

Paul D. Hanna, Dec 12 2006

Keywords

• nonn

Comments

Triangle A125806 gives the sum of squared coefficients of q in the corresponding q-binomial coefficients.

Crossrefs

Cf. A125806 (triangle); A063075, A125807, A125808.

Programs

PARI

{a(n)=sum(k=0,n,sum(i=0,(n-k)*k, polcoeff(if(n==0,1,prod(j=n-k+1,n,1-q^j)/prod(j=1,k,1-q^j)),i)^2))}