OFFSET
1,1
COMMENTS
Prime divisors taken without multiplicity. - Harvey P. Dale, Dec 27 2018
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
Jean-Marie de Koninck and Florian Luca, Integers divisible by sums of powers of their prime factors, Journal of Number Theory, Volume 128, Issue 3, March 2008, Pages 557-563.
MATHEMATICA
dssQ[n_]:=Module[{pf=FactorInteger[n][[All, 1]]}, !PrimePowerQ[ n] && Divisible[ n, Total[pf]]&&Divisible[n, Total[pf^2]]]; Select[ Range[ 960000], dssQ] (* Harvey P. Dale, Dec 27 2018 *)
PROG
(PARI) isok(n) = my(f = factor(n)[, 1]); (#f>2) && ((n % vecsum(f)) == 0) && ((n % sum(k=1, #f, f[k]^2)) == 0);
CROSSREFS
KEYWORD
nonn
AUTHOR
Michel Marcus, Feb 04 2016
STATUS
approved