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%I #36 Sep 20 2023 05:49:05
%S 1,1,1,1,1,1,2,1,1,2,1,1,2,2,2,4,4,2,1,4,2,2,3,2,1,4,3,3,1,3,4,5,4,5,
%T 4,3,3,4,7,2,5,4,4,2,4,3,4,2,3,7,4,2,4,2,3,2,4,3,4,5,3,4,4,2,1,2,4,6,
%U 4,3,3,4,4,6,6,6,5,3,6,4,5,3,3,5,3,4,3,4,7,6,4,3,4,2,3,3,2,2,5,2,3,3,6,4,3,3,2,3,2,6
%N Number of distinct prime factors of A104365(n) = A104350(n) + 1.
%H Max Alekseyev, <a href="/A104368/b104368.txt">Table of n, a(n) for n = 1..158</a> (terms 142..151 from Tyler Busby)
%H Reinhard Zumkeller, <a href="/A104350/a104350.txt">Products of largest prime factors of numbers <= n</a>
%F a(n) = A001221(A104365(n)).
%t A104350[n_] := Product[FactorInteger[k][[-1, 1]], {k, 1, n}]; PrimeNu[
%t Table[A104350[n] + 1, {n, 2, 50}]] (* _G. C. Greubel_, May 10 2017 *)
%Y Cf. A001221, A054988, A066856, A104350, A104359, A104360, A104365, A104366, A104367, A104369, A104370, A104371, A104372.
%K nonn
%O 1,7
%A _Reinhard Zumkeller_, Mar 06 2005
%E a(51)-a(76) from _Amiram Eldar_, Feb 12 2020
%E a(77)-a(81) from _Jinyuan Wang_, Apr 02 2020
%E Terms a(82) onward from _Max Alekseyev_, Oct 03 2022
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