cp's OEIS Frontend

A115959 Numbers k having exactly 5 distinct prime factors, the largest of which is greater than or equal to sqrt(k) (i.e., sqrt(k)-rough numbers with exactly 5 distinct prime factors).

%I A115959 #12 Aug 04 2025 20:20:23
%S A115959 44310,46830,47670,48090,48930,50190,50610,52710,53970,55230,56490,
%T A115959 56910,58170,59010,59430,61530,64470,65310,65730,66570,69510,70770,
%U A115959 72870,73290,74130,75390,77070,78330,79590,80430,81690,83370,84210
%N A115959 Numbers k having exactly 5 distinct prime factors, the largest of which is greater than or equal to sqrt(k) (i.e., sqrt(k)-rough numbers with exactly 5 distinct prime factors).
%H A115959 Robert Israel, <a href="/A115959/b115959.txt">Table of n, a(n) for n = 1..10000</a>
%e A115959 46830 is in the sequence because it has 5 distinct prime factors (2, 3, 5, 7 and 223) and 223 > sqrt(46830).
%p A115959 with(numtheory): a:=proc(n) if nops(factorset(n))=5 and factorset(n)[5]^2>=n then n else fi end: seq(a(n),n=1..93000);
%Y A115959 Cf. A115956, A115957, A115958, A115960, A115961.
%K A115959 nonn
%O A115959 1,1
%A A115959 _Emeric Deutsch_, Feb 02 2006