OFFSET
1,1
COMMENTS
Koninck & Luca prove that this set is infinite. - Charles R Greathouse IV, Feb 03 2016
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
Jean-Marie de Koninck, Florian Luca, Integers divisible by sums of powers of their prime factors, Journal of Number Theory, Volume 128, Issue 3 (March 2008), pp. 557-563.
EXAMPLE
The prime factors of 480 are 2, 3 and 5. The sum of their cubes is 2^3+3^3+5^3=160, and 480 is divisible by 160.
MATHEMATICA
Select[Range[10^4], Length[(p = FactorInteger[#][[;; , 1]])] > 1 && Divisible[#, Total[p^3]] &] (* Amiram Eldar, Sep 05 2019 *)
PROG
(PARI) isok(n) = my(f = factor(n)[, 1]) ; (#f>2) && ((n % sum(k=1, #f, f[k]^3)) == 0);
CROSSREFS
KEYWORD
nonn
AUTHOR
Michel Marcus, Feb 03 2016
STATUS
approved