OFFSET
0,3
COMMENTS
Multiplicative because A013961 is. - Andrew Howroyd, Jul 25 2018
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..10000
FORMULA
a(n) = n*A013961(n) for n > 0.
Sum_{k=1..n} a(k) ~ zeta(14) * n^15 / 15. - Amiram Eldar, Sep 06 2023
From Amiram Eldar, Oct 30 2023: (Start)
Multiplicative with a(p^e) = p^e * (p^(13*e+13)-1)/(p^13-1).
Dirichlet g.f.: zeta(s-1)*zeta(s-14). (End)
MATHEMATICA
Table[n * DivisorSigma[13, n], {n, 0, 17}] (* Amiram Eldar, Sep 06 2023 *)
PROG
(PARI) a(n) = if(n < 1, 0, n*sigma(n, 13)) \\ Andrew Howroyd, Jul 25 2018
CROSSREFS
KEYWORD
nonn,easy,mult,changed
AUTHOR
Seiichi Manyama, Feb 19 2017
STATUS
approved