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A111060 a(n) = sum of primes dividing the n-th squarefree positive integer.

%I A111060 #13 Dec 26 2017 01:30:09
%S A111060 0,2,3,5,5,7,7,11,13,9,8,17,19,10,13,23,15,29,10,31,14,19,12,37,21,16,
%T A111060 41,12,43,25,47,20,53,16,22,31,59,61,33,18,16,67,26,14,71,73,39,18,18,
%U A111060 79,43,83,22,45,32,89,20,34,49,24,97,101,22,103,15,55,107,109,18,40,113
%N A111060 a(n) = sum of primes dividing the n-th squarefree positive integer.
%C A111060 For n > 1: sum of row n in A265668. - _Reinhard Zumkeller_, Dec 13 2015
%H A111060 Reinhard Zumkeller, <a href="/A111060/b111060.txt">Table of n, a(n) for n = 1..10000</a>
%F A111060 a(n) = A008472(A005117(n)) = A001414(A005117(n)).
%e A111060 Since the 5th squarefree positive integers is 6 = 2*3, the 5th term of the sequence is 2 + 3 = 5.
%t A111060 Table[DivisorSum[n, # &, PrimeQ], {n, Select[Range@ 113, SquareFreeQ]}] (* _Michael De Vlieger_, Dec 23 2017 *)
%o A111060 (PARI) {for(n=1,113,if(issquarefree(n),f=factor(n)[,1];print1(sum(j=1,length(f),f[j]),",")))}
%o A111060 (Haskell)
%o A111060 a111060 1 = 0
%o A111060 a111060 n = sum $ a265668_row n -- _Reinhard Zumkeller_, Dec 13 2015
%Y A111060 Cf. A001414, A005117, A008472, A265668.
%K A111060 nonn
%O A111060 1,2
%A A111060 _Leroy Quet_, Oct 07 2005
%E A111060 More terms from _Klaus Brockhaus_, Oct 08 2005