OFFSET
0,2
LINKS
Robert Israel, Table of n, a(n) for n = 0..300
Eric Weisstein's World of Mathematics, q-Factorial.
FORMULA
a(n) = [q^(n+2)] Product_{i=1..n+2} { (1-q^i)/(1-q) }^2.
MAPLE
P:= (1+q)^2: A[0]:= 1:
for n from 1 to 50 do
P:= normal(P * (1-q^(n+2))^2/(1-q)^2);
A[n]:= coeff(P, q, n+2);
od:
seq(A[i], i=0..50); # Robert Israel, Jun 25 2018
PROG
(PARI) a(n)=polcoeff(prod(i=1, n+2, (1-x^i)/(1-x))^2, n+2)
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Apr 07 2007
STATUS
approved