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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A380264 a(n) is the numerator of the mean value of A051903(k) at the range k = 1..n.

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%I A380264 #11 Feb 16 2025 08:34:07
%S A380264 0,1,2,1,1,1,1,5,4,13,14,4,17,9,19,23,24,13,27,29,10,31,32,35,37,19,
%T A380264 41,43,44,3,46,51,52,53,54,14,57,29,59,31,63,32,65,67,23,35,71,25,11,
%U A380264 79,80,41,83,43,87,45,91,46,93,19,96,97,11,105,106,107,108,55
%N A380264 a(n) is the numerator of the mean value of A051903(k) at the range k = 1..n.
%H A380264 Amiram Eldar, <a href="/A380264/b380264.txt">Table of n, a(n) for n = 1..10000</a>
%H A380264 Ivan Niven, <a href="https://doi.org/10.1090/S0002-9939-1969-0241373-5">Averages of Exponents in Factoring Integers</a>, Proc. Amer. Math. Soc., Vol. 22, No. 2 (1969), pp. 356-360.
%H A380264 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/NivensConstant.html">Niven's Constant</a>.
%H A380264 Wikipedia, <a href="https://en.wikipedia.org/wiki/Niven%27s_constant">Niven's constant</a>.
%F A380264 a(n) = numerator((Sum_{k=1..n} A051903(k))/n).
%F A380264 a(n)/A380265(n) = A129132(n)/n.
%F A380264 Limit_{n->oo} a(n)/A380265(n) = c, where c is Niven's constant (A033150).
%F A380264 abs(a(n)/A380265(n) - c) <= 3*log_2(n)/sqrt(n).
%e A380264 Fractions begin with 0, 1/2, 2/3, 1, 1, 1, 1, 5/4, 4/3, 13/10, 14/11, 4/3, ...
%t A380264 f[n_] := Max[FactorInteger[n][[;;, 2]]]; f[1] = 0; With[{m = 100}, Numerator[Accumulate[Array[f, m]] / Range[m]]]
%o A380264 (PARI) lista(nmax) = {my(s = 0); print1(0, ", "); for(n = 2, nmax, s += vecmax(factor(n)[,2]);  print1(numerator(s/n), ", "));}
%Y A380264 Cf. A033150, A051903, A129132, A359071, A359072, A380265 (denominators).
%K A380264 nonn,easy,frac
%O A380264 1,3
%A A380264 _Amiram Eldar_, Jan 18 2025