OFFSET
1,3
LINKS
N. J. A. Sloane, Table of n, a(n) for n = 1..10000
FORMULA
G.f.: (1/(1 - x)) * Sum_{k>=1} 2^(k-1) * x^prime(k) / (1 - x^prime(k)). - Ilya Gutkovskiy, Aug 18 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jun 24 2017
STATUS
approved