0,2

G.f.: A(x) = (1-2x)/(1-x)^3 + x*A(x)^3.

a(1)=1+1=2, a(2)=0+3+3=6, a(3)=-2+3+15+12=28, a(4)=-5-5+30+84+55=159.

Cf. A086632 (table).

Sequence in context: A047125 A065577 A004984 this_sequence A109570 A088501 A140092

Adjacent sequences: A086630 A086631 A086632 this_sequence A086634 A086635 A086636

nonn

Paul D. Hanna (pauldhanna(AT)juno.com), Jul 24 2003