1,1

a(n) = sum r=1..n r*product j=0..(r-1) (q^n-q^j)^2/(q^r-q^j) with q=4.

Cf. A086190, A086098.

Sequence in context: A120061 A137023 A087771 this_sequence A092052 A139999 A094454

Adjacent sequences: A086204 A086205 A086206 this_sequence A086208 A086209 A086210

nonn

Yuval Dekel (dekelyuval(AT)hotmail.com), Aug 27 2003