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Numbers not exceeding the 4th power of their smallest prime-factor.
4

%I #9 Feb 06 2015 10:53:28

%S 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,19,21,23,25,27,29,31,33,35,

%T 37,39,41,43,45,47,49,51,53,55,57,59,61,63,65,67,69,71,73,75,77,79,81,

%U 83,85,89,91,95,97,101,103,107,109,113,115,119,121,125,127,131,133

%N Numbers not exceeding the 4th power of their smallest prime-factor.

%C a(n) <= A020639(a(n))^4 = A088379(a(n)); complement of A088383;

%C a(n) < A088383(k) for n <= 67, a(n) > A088383(k) for n > 67.

%H Reinhard Zumkeller, <a href="/A088382/b088382.txt">Table of n, a(n) for n = 1..10000</a>

%t Select[Range[200],#<=FactorInteger[#][[1,1]]^4&] (* _Harvey P. Dale_, Jan 25 2015 *)

%o (Haskell)

%o a088382 n = a088382_list !! (n-1)

%o a088382_list = [x | x <- [1..], x <= a020639 x ^ 4]

%o -- _Reinhard Zumkeller_, Feb 06 2015

%Y Cf. A088380, A000430, A020639, A088379, A088383.

%K nonn

%O 1,2

%A _Reinhard Zumkeller_, Sep 28 2003