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%I #9 Apr 28 2022 15:51:57
%S 1,2,3,4,5,6,7,8,9,11,13,15,17,19,21,23,25,27,29,31,35,37,41,43,47,49,
%T 53,55,59,61,65,67,71,73,77,79,83,85,89,91,95,97,101,103,107,109,113,
%U 115,119,121,125,127,131,133,137,139,143,149,151,157,161,163,167,169
%N Numbers not exceeding the cube of their smallest prime-factor.
%C a(n) <= A020639(a(n))^3 = A088378(a(n)); complement of A088381;
%C a(n) < A088381(k) for n <= 28, a(n) > A088381(k) for n > 28.
%H Reinhard Zumkeller, <a href="/A088380/b088380.txt">Table of n, a(n) for n = 1..10000</a>
%t Select[Range[200],#<=FactorInteger[#][[1,1]]^3&] (* _Harvey P. Dale_, Apr 28 2022 *)
%o (Haskell)
%o a088380 n = a088382_list !! (n-1)
%o a088380_list = [x | x <- [1..], x <= a020639 x ^ 3]
%o -- _Reinhard Zumkeller_, Feb 06 2015
%Y Cf. A000430, A088382, A020639, A088378, A088381.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Sep 28 2003