OFFSET
0,2
FORMULA
a(n) = Sum_{k=0..n} C(k)*8^k, with C(n) = A000108(n).
G.f.: c(8*x)/(1-x), where c(x) = (1-sqrt(1-4*x))/(2*x) is the o.g.f. of Catalan numbers A000108.
Conjecture: (n+1)*a(n) +3*(-11*n+5)*a(n-1) +16*(2*n-1)*a(n-2)=0. - R. J. Mathar, Jun 08 2016
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Wolfdieter Lang, Oct 31 2005
STATUS
approved