OFFSET
1,2
LINKS
Seiichi Manyama, Table of n, a(n) for n = 1..10000
László Tóth, Menon's identity and arithmetical sums representing functions of several variables, Rend. Sem. Mat. Univ. Politec. Torino, Vol. 69, No. 1 (2011), pp. 97-110.
FORMULA
From Amiram Eldar, May 24 2024: (Start)
Multiplicative with a(p^e) = p^e * (1 + ((p-1)/p) * Sum_{i=1..e} p^(floor(2*i/3))). (End)
MATHEMATICA
a[n_] := Sum[GCD[k^3, n], {k, 1, n}]; Array[a, 100] (* Amiram Eldar, May 24 2024 *)
PROG
(PARI) a(n) = sum(k=1, n, gcd(k^3, n));
CROSSREFS
KEYWORD
nonn,mult
AUTHOR
Seiichi Manyama, May 15 2024
STATUS
approved