OFFSET
1,2
LINKS
Alois P. Heinz, Table of n, a(n) for n = 1..50
MAPLE
MATHEMATICA
Sum[q^(k (n - k)) QBinomial[n, k, q], {k, 1, n}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Alexander Gruber, Feb 12 2013
STATUS
approved