OFFSET
1,2
COMMENTS
Here prime powers means the numbers in A246655.
For p prime, p^(k-1) is a term in A003601 if and only if (p^k-1)/(p-1) is divisible by k. So this sequence is (A107924 U A107925) \ {p^((k-1)/2): p prime, k odd, k | (p^k-1)/(p-1)}.
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
EXAMPLE
MATHEMATICA
Select[Range[1500], !PrimePowerQ[#] && Divisible @@ DivisorSigma[{1, 0}, #^2] &] (* Amiram Eldar, Jul 19 2024 *)
PROG
(PARI) isA353062(n) = sigma(n^2)%numdiv(n^2)==0 && !isprimepower(n)
CROSSREFS
KEYWORD
nonn
AUTHOR
Jianing Song, Apr 20 2022
STATUS
approved