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%I #7 Nov 18 2018 09:10:25
%S 2,2,2,2,2,2,2,2,2,2,2,2,3,2,2,2,2,2,2,2,3,2,2,2,2,2,2,2,2,2,2,2,2,3,
%T 2,2,2,3,2,2,3,2,2,2,2,2,3,2,2,3,2,2,2,2,3,2,2,2,2,2,2,2,2,2,3,2,3,2,
%U 2,3,2,2,3,2,2,2,2,2,3,2,2,2,3,2,3,3,2,2,2,2,3,3,2,2,2,2,2,2,2,2,3,2,2,3,2
%N Number of distinct prime factors of numbers that are not prime powers.
%H Harvey P. Dale, <a href="/A074594/b074594.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = A001221(A024619(n)).
%t PrimeNu/@Select[Range[2,300],!PrimePowerQ[#]&] (* _Harvey P. Dale_, Nov 18 2018 *)
%Y Cf. A074595, A074592, A074593.
%K nonn
%O 1,1
%A _Reinhard Zumkeller_, Aug 25 2002