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A088381 Numbers greater than the cube of their smallest prime factor.

%I A088381 #22 Feb 12 2025 11:55:22
%S A088381 10,12,14,16,18,20,22,24,26,28,30,32,33,34,36,38,39,40,42,44,45,46,48,
%T A088381 50,51,52,54,56,57,58,60,62,63,64,66,68,69,70,72,74,75,76,78,80,81,82,
%U A088381 84,86,87,88,90,92,93,94,96,98,99,100,102,104,105,106,108,110,111,112
%N A088381 Numbers greater than the cube of their smallest prime factor.
%C A088381 a(n) > A020639(a(n))^3 = A088378(a(n)); complement of A088380;
%C A088381 a(n) > A088380(k) for n <= 28, a(n) < A088380(k) for n > 28.
%H A088381 Robert Israel, <a href="/A088381/b088381.txt">Table of n, a(n) for n = 1..10000</a>
%p A088381 filter:= n -> n > min(numtheory:-factorset(n))^3:
%p A088381 select(filter, [$2..200]); # _Robert Israel_, Aug 11 2020
%o A088381 (Haskell)
%o A088381 a088381 n = a088381_list !! (n-1)
%o A088381 a088381_list = filter f [1..] where
%o A088381                       f x = p ^ 2 < div x p  where p = a020639 x
%o A088381 -- _Reinhard Zumkeller_, Jan 08 2015
%o A088381 (PARI) isok(n) = n > factor(n)[1,1]^3; \\ _Michel Marcus_, Jan 08 2015
%Y A088381 Cf. A080257, A088378, A088380, A088383.
%Y A088381 Cf. A020639, A138511 (subsequence).
%Y A088381 Positions of numbers greater than 3 in A307908.
%K A088381 nonn
%O A088381 1,1
%A A088381 _Reinhard Zumkeller_, Sep 28 2003