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A111060 a(n) = sum of primes dividing the n-th squarefree positive integer. 2
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, 41, 12, 43, 25, 47, 20, 53, 16, 22, 31, 59, 61, 33, 18, 16, 67, 26, 14, 71, 73, 39, 18, 18, 79, 43, 83, 22, 45, 32, 89, 20, 34, 49, 24, 97, 101, 22, 103, 15, 55, 107, 109, 18, 40, 113 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

For n > 1: sum of row n in A265668. - Reinhard Zumkeller, Dec 13 2015

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

FORMULA

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

EXAMPLE

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

MATHEMATICA

Table[DivisorSum[n, # &, PrimeQ], {n, Select[Range@ 113, SquareFreeQ]}] (* Michael De Vlieger, Dec 23 2017 *)

PROG

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

(Haskell)

a111060 1 = 0

a111060 n = sum $ a265668_row n -- Reinhard Zumkeller, Dec 13 2015

CROSSREFS

Cf. A001414, A005117, A008472, A265668.

Sequence in context: A123318 A186698 A234345 * A082432 A336298 A037153

Adjacent sequences:  A111057 A111058 A111059 * A111061 A111062 A111063

KEYWORD

nonn

AUTHOR

Leroy Quet, Oct 07 2005

EXTENSIONS

More terms from Klaus Brockhaus, Oct 08 2005

STATUS

approved

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Last modified April 13 07:25 EDT 2021. Contains 342935 sequences. (Running on oeis4.)