A323171 Numerator of the average of distinct prime factors of n (A008472(n)/A001221(n)).

2, 3, 2, 5, 5, 7, 2, 3, 7, 11, 5, 13, 9, 4, 2, 17, 5, 19, 7, 5, 13, 23, 5, 5, 15, 3, 9, 29, 10, 31, 2, 7, 19, 6, 5, 37, 21, 8, 7, 41, 4, 43, 13, 4, 25, 47, 5, 7, 7, 10, 15, 53, 5, 8, 9, 11, 31, 59, 10, 61, 33, 5, 2, 9, 16, 67, 19, 13, 14, 71, 5, 73, 39, 4, 21, 9, 6, 79, 7, 3, 43, 83, 4, 11, 45, 16, 13, 89, 10, 10, 25, 17, 49, 12, 5

Offset: 2

Author

Antti Karttunen, Jan 05 2019

Keywords

• nonn
• easy
• frac

Examples

			Fractions begins with 2, 3, 2, 5, 5/2, 7, 2, 3, 7/2, 11, 5/2, 13, ...
		

Links

• Antti Karttunen, Table of n, a(n) for n = 2..20000

Crossrefs

Cf. A323172 (denominators).

Cf. A001221, A008472, A123528.

Programs

Mathematica

a[n_] := Numerator[Mean[FactorInteger[n][[;; , 1]]]]; Array[a, 100, 2] (* Amiram Eldar, Sep 17 2024 *)

PARI

A008472(n) = vecsum(factor(n)[, 1]); \\ From A008472
A323171(n) = (numerator(A008472(n)/omega(n)));