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%I #32 Sep 01 2022 14:28:47
%S 12,18,20,24,28,40,44,45,48,50,52,54,56,60,63,68,72,75,76,80,84,88,90,
%T 92,96,98,99,104,108,112,116,117,120,124,126,132,135,136,140,144,147,
%U 148,150,152,153,156,160,162,164,168,171,172,175,176,180,184,188,189
%N Numbers with different exponents in their prime factorizations.
%C Former name: Numbers k such that k/(largest power of squarefree kernel of k) is larger than 1.
%C Complement of A072774 (powers of squarefree numbers).
%C Also numbers k = p(1)^alpha(1)* ... * p(r)^alpha(r) such that RootMeanSquare(alpha(1), ..., alpha(r)) is not an integer. - _Ctibor O. Zizka_, Sep 19 2008
%H Donald Alan Morrison, <a href="/A059404/b059404.txt">Table of n, a(n) for n = 1..10000</a>
%H Donald Alan Morrison, <a href="/A059404/a059404.txt">Sage program</a>
%F A062760(a(n)) > 1, i.e., a(n)/(A007947(a(n))^A051904(a(n)) = a(n)/A062759(n) > 1.
%F A071625(a(n)) > 1. - _Michael S. Branicky_, Sep 01 2022
%e 440 is in the sequence because 440 = 2^3*5*11 and it has two distinct exponents, 3 and 1.
%o (PARI) is(n)=#Set(factor(n)[,2])>1 \\ _Charles R Greathouse IV_, Sep 18 2015
%o (Python)
%o from sympy import factorint
%o def ok(n): return len(set(factorint(n).values())) > 1
%o print([k for k in range(190) if ok(k)]) # _Michael S. Branicky_, Sep 01 2022
%Y Cf. A003557, A007947, A051904, A062759, A062760, A071625.
%K nonn,easy
%O 1,1
%A _Labos Elemer_, Jul 18 2001
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