0,2

a(n)=sum(C(k)*7^k, k=0..n), n>=0, with C(n):=A000108(n).

G.f.: c(7*x)/(1-x), where c(x):=(1-sqrt(1-4*x))/(2*x) is the o.g.f. of Catalan numbers A000108.

Eighth column (m=7) of triangle A112705.

Sequence in context: A055406 A155632 A129278 this_sequence A099695 A000845 A027013

Adjacent sequences: A112698 A112699 A112700 this_sequence A112702 A112703 A112704

nonn,easy

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