OFFSET
1,3
MATHEMATICA
PROG
(Magma) [&+[MoebiusMu(Gcd(n, k))*Lcm(n, k)/ Gcd(n, k):k in [1..n]]:n in [1..50]]; // Marius A. Burtea, Feb 18 2020
(PARI) a(n) = sum(k=1, n, moebius(gcd(n, k))*lcm(n, k)/gcd(n, k)); \\ Michel Marcus, Feb 18 2020
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Feb 18 2020
STATUS
approved