OFFSET
1,2
EXAMPLE
sigma(1)^tau(1) + sigma(2)^tau(2) + sigma(3)^tau(3) + sigma(4)^tau(4) + sigma(5)^tau(5) = 1^1 + 3^2 + 4^2 + 7^3 + 6^2 = 1 + 9 + 16 + 343 + 36 = 405 and 405 / 5 = 81.
MAPLE
with(numtheory): P:=proc(q) local a, n; a:=0;
for n from 1 to q do a:=a+sigma(n)^tau(n);
if a mod n=0 then print(n); fi; od; end: P(10^6);
PROG
(PARI) for(n=1, 1e4, if(sum(k=1, n, sigma(k)^numdiv(k))%n==0, print1(n", "))) \\ Altug Alkan, Nov 13 2015
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Paolo P. Lava, Nov 13 2015
EXTENSIONS
Incorrect terms removed by and more terms from Jinyuan Wang, Feb 18 2021
STATUS
approved