0,2

a(n)=sum(C(k)*9^k, k=0..n), n>=0, with C(n):=A000108(n).

G.f.: c(9*x)/(1-x), where c(x):=(1-sqrt(1-4*x))/(2*x) is the o.g.f. of Catalan numbers A000108.

Tenth column (m=9) of triangle A112705.

Sequence in context: A119043 A133273 A116636 this_sequence A132676 A078516 A144516

Adjacent sequences: A112700 A112701 A112702 this_sequence A112704 A112705 A112706

nonn,easy

Wolfdieter Lang (wolfdieter.lang_AT_physik_DOT_uni-karlsruhe_DOT_de), Oct 31 2005