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%I #22 Sep 08 2022 08:46:21
%S 2,3,5,7,11,13,17,19,23,25,29,31,37,41,43,47,49,53,59,61,67,71,73,77,
%T 79,83,89,91,97,101,103,107,109,113,119,121,127,131,137,139,143,149,
%U 151,157,163,167,169,173,179,181,187,191,193,197,199,209,211,221,223,227,229,233
%N Integers k > 1 whose least prime factor is greater than log_2(k).
%C p^k is a member if p is prime and 1 <= k < p/log_2(p).
%C p*q is a member if p and q are primes and p < q < 2^p/p.
%H Robert Israel, <a href="/A308966/b308966.txt">Table of n, a(n) for n = 1..10000</a>
%e a(24) = 77 is a member because its least prime factor is 7, and 7 > log_2(77) ~= 6.2668.
%p filter:= proc(n) 2^min(numtheory:-factorset(n)) > n end proc:
%p select(filter, [$2..1000]);
%t filterQ[n_] := FactorInteger[n][[1, 1]] > Log[2, n];
%t Select[Range[2, 1000], filterQ] (* _Jean-François Alcover_, Jul 31 2020 *)
%o (Magma) [k:k in [2..250]| PrimeDivisors(k)[1] gt Log(2,k)]; // _Marius A. Burtea_, Jul 03 2019
%Y Cf. A020639.
%K nonn
%O 1,1
%A _Robert Israel_, Jul 03 2019
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