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%I #15 Feb 16 2021 04:33:06
%S 1,2,3,4,5,7,9,11,12,13,17,18,19,20,23,25,28,29,31,37,41,43,44,45,47,
%T 49,50,52,53,59,61,63,67,68,71,73,75,76,79,83,89,92,97,98,99,101,103,
%U 107,109,113,116,117,121,124,127,131,137,139,147,148,149,151,153,157,163,164,167,169,171
%N Cubefree numbers which in their canonical prime factorization have mutually distinct exponents.
%H Amiram Eldar, <a href="/A230843/b230843.txt">Table of n, a(n) for n = 1..10000</a>
%t q[n_] := Max[(e = FactorInteger[n][[;; , 2]])] < 3 && Length @ Union[e] == Length[e]; Select[Range[200], q] (* _Amiram Eldar_, Feb 16 2021 *)
%Y Intersection of A004709 and A130091.
%Y Disjoint union of {1}, A000040, A001248 and A054753.
%K nonn,easy
%O 1,2
%A _Gerasimov Sergey_, Oct 31 2013
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