0,2

G.f.: (1-2x)/(1-10x+20x^2); a(n)=(5+sqrt(5))^n(1/2+3sqrt(5)/10)+(1/2-3sqrt(5)/10)(5-sqrt(5))^n; a(n)=2^n*A039717(n).

Cf. A000045.

Sequence in context: A081158 A002927 A126640 this_sequence A094169 A129325 A001267

Adjacent sequences: A093129 A093130 A093131 this_sequence A093133 A093134 A093135

easy,nonn

Paul Barry (pbarry(AT)wit.ie), Mar 23 2004