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%I #19 Feb 24 2024 01:02:52
%S 15,20,24,35,42,54,66,72,95,98,100,104,108,110,114,119,120,126,132,
%T 135,140,143,160,168,189,195,207,209,216,220,224,258,264,270,276,287,
%U 290,294,319,322,323,351,360,363,375,377,378,384,392,432,440,456,459,464
%N Numbers k such that the sum of prime divisors of k divides the sum of divisors of k.
%H Amiram Eldar, <a href="/A070222/b070222.txt">Table of n, a(n) for n = 1..10000</a>
%e The sum of divisors of 132 is sigma(132) = 336; prime divisors of 132 are 2,3,11 and (336)/(2+3+11) = 336/16 = 21 hence 132 is in the sequence.
%t Select[Range[2,464], IntegerQ[DivisorSigma[1,#]/Total[First/@FactorInteger[#]]] &] (* _Jayanta Basu_, May 16 2013 *)
%o (PARI) for(n=2,700,if(sigma(n)%sumdiv(n,d,isprime(d)*d)==0,print1(n,",")))
%Y Cf. A000203, A008472.
%Y A037074 is a subsequence. - _Amiram Eldar_, Aug 08 2020
%K easy,nonn
%O 1,1
%A _Benoit Cloitre_, May 07 2002