OFFSET
1,2
FORMULA
If p is prime, a(p) = A121706(p) + p.
MATHEMATICA
a[n_] := Sum[k^(n/GCD[k, n]), {k, 1, n}]; Array[a, 18] (* Amiram Eldar, Mar 10 2021 *)
PROG
(PARI) a(n) = sum(k=1, n, k^(n/gcd(k, n)));
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Seiichi Manyama, Mar 10 2021
STATUS
approved