OFFSET
1,2
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
FORMULA
a(n) = Sum_{k=1..n} A019554(k) ~ 3*zeta(3)*n^2 / Pi^2. - Vaclav Kotesovec, Sep 18 2020 [Copied from A019554]
PROG
(PARI) a(n) = sum(k=1, n, k/core(k, 1)[2]); \\ Michel Marcus, Jul 27 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jul 27 2021
STATUS
approved