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A125809 Row sums of triangle A125806. 3
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

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

LINKS

Table of n, a(n) for n=0..26.

PROG

(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))}

CROSSREFS

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

Sequence in context: A176720 A088457 A006786 * A245176 A000117 A308030

Adjacent sequences:  A125806 A125807 A125808 * A125810 A125811 A125812

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Dec 12 2006

STATUS

approved

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Last modified April 6 18:49 EDT 2020. Contains 333286 sequences. (Running on oeis4.)