OFFSET
1,1
LINKS
Andrew Howroyd, Table of n, a(n) for n = 1..200
C. G. Bower, Transforms (2)
FORMULA
G.f.: (5*x*(1+3*x+x^2)/((1-x)*(1-6*x^2)) + Sum_{d>0} phi(d)*log((1-x^d)/(1-6*x^d))/d)/2. - Andrew Howroyd, Jun 20 2018
PROG
(PARI) seq(n)={Vec(5*x*(1+3*x+x^2)/((1-x)*(1-6*x^2)) + sum(d=1, n, eulerphi(d)/d*log((1-x^d)/(1-6*x^d) + O(x*x^n))))/2} \\ Andrew Howroyd, Jun 20 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
Terms a(21) and beyond from Andrew Howroyd, Jun 20 2018
STATUS
approved