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A115959 Numbers n having exactly 5 distinct prime factors, the largest of which is greater than or equal to sqrt(n) (i.e., sqrt(n)-rough numbers with exactly 5 distinct prime factors). 6

%I #9 Nov 03 2020 16:10:39

%S 44310,46830,47670,48090,48930,50190,50610,52710,53970,55230,56490,

%T 56910,58170,59010,59430,61530,64470,65310,65730,66570,69510,70770,

%U 72870,73290,74130,75390,77070,78330,79590,80430,81690,83370,84210

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

%H Robert Israel, <a href="/A115959/b115959.txt">Table of n, a(n) for n = 1..10000</a>

%e 46830 is in the sequence because it has 5 distinct prime factors (2, 3, 5, 7 and 223) and 223 > sqrt(46830).

%p 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 Cf. A115956, A115957, A115958, A115960, A115961.

%K nonn

%O 1,1

%A _Emeric Deutsch_, Feb 02 2006

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Last modified April 18 22:18 EDT 2024. Contains 371782 sequences. (Running on oeis4.)