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A326567 Numerator of the average of the multiset of prime indices of n. 18
1, 2, 1, 3, 3, 4, 1, 2, 2, 5, 4, 6, 5, 5, 1, 7, 5, 8, 5, 3, 3, 9, 5, 3, 7, 2, 2, 10, 2, 11, 1, 7, 4, 7, 3, 12, 9, 4, 3, 13, 7, 14, 7, 7, 5, 15, 6, 4, 7, 9, 8, 16, 7, 4, 7, 5, 11, 17, 7, 18, 6, 8, 1, 9, 8, 19, 3, 11, 8, 20, 7, 21, 13, 8, 10, 9, 3, 22, 7, 2, 7 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,2

COMMENTS

A prime index of n is a number m such that prime(m) divides n. The multiset of prime indices of n is row n of A112798.

LINKS

Table of n, a(n) for n=2..82.

EXAMPLE

The prime indices of 12 are {1,1,2}, with average 4/3, so a(12) = 4.

MATHEMATICA

Table[Numerator[Sum[q[[2]]*PrimePi[q[[1]]], {q, FactorInteger[n]}]/PrimeOmega[n]], {n, 2, 100}]

CROSSREFS

Cf. A001222, A001414, A056239, A067629, A112798, A123528/A123529, A289508, A289509, A290103, A316413, A326568.

Sequence in context: A245367 A304740 A326619 * A066328 A330417 A330415

Adjacent sequences:  A326564 A326565 A326566 * A326568 A326569 A326570

KEYWORD

nonn,frac

AUTHOR

Gus Wiseman, Jul 13 2019

STATUS

approved

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Last modified November 27 05:27 EST 2020. Contains 338678 sequences. (Running on oeis4.)