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

%I A323171 #11 Sep 17 2024 04:03:39
%S A323171 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,
%T A323171 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,
%U A323171 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
%N A323171 Numerator of the average of distinct prime factors of n (A008472(n)/A001221(n)).
%H A323171 Antti Karttunen, <a href="/A323171/b323171.txt">Table of n, a(n) for n = 2..20000</a>
%e A323171 Fractions begins with 2, 3, 2, 5, 5/2, 7, 2, 3, 7/2, 11, 5/2, 13, ...
%t A323171 a[n_] := Numerator[Mean[FactorInteger[n][[;; , 1]]]]; Array[a, 100, 2] (* _Amiram Eldar_, Sep 17 2024 *)
%o A323171 (PARI)
%o A323171 A008472(n) = vecsum(factor(n)[, 1]); \\ From A008472
%o A323171 A323171(n) = (numerator(A008472(n)/omega(n)));
%Y A323171 Cf. A323172 (denominators).
%Y A323171 Cf. A001221, A008472, A123528.
%K A323171 nonn,easy,frac
%O A323171 2,1
%A A323171 _Antti Karttunen_, Jan 05 2019