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A111060 a(n) = sum of primes dividing the n-th squarefree positive integer. 2

%I

%S 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 41,12,43,25,47,20,53,16,22,31,59,61,33,18,16,67,26,14,71,73,39,18,18,

%U 79,43,83,22,45,32,89,20,34,49,24,97,101,22,103,15,55,107,109,18,40,113

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

%C For n > 1: sum of row n in A265668. - _Reinhard Zumkeller_, Dec 13 2015

%H Reinhard Zumkeller, <a href="/A111060/b111060.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = A008472(A005117(n)) = A001414(A005117(n)).

%e Since the 5th squarefree positive integers is 6 = 2*3, the 5th term of the sequence is 2 + 3 = 5.

%t Table[DivisorSum[n, # &, PrimeQ], {n, Select[Range@ 113, SquareFreeQ]}] (* _Michael De Vlieger_, Dec 23 2017 *)

%o (PARI) {for(n=1,113,if(issquarefree(n),f=factor(n)[,1];print1(sum(j=1,length(f),f[j]),",")))}

%o (Haskell)

%o a111060 1 = 0

%o a111060 n = sum $ a265668_row n -- _Reinhard Zumkeller_, Dec 13 2015

%Y Cf. A001414, A005117, A008472, A265668.

%K nonn

%O 1,2

%A _Leroy Quet_, Oct 07 2005

%E More terms from _Klaus Brockhaus_, Oct 08 2005

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Last modified April 23 00:56 EDT 2021. Contains 343197 sequences. (Running on oeis4.)