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).
44310, 46830, 47670, 48090, 48930, 50190, 50610, 52710, 53970, 55230, 56490, 56910, 58170, 59010, 59430, 61530, 64470, 65310, 65730, 66570, 69510, 70770, 72870, 73290, 74130, 75390, 77070, 78330, 79590, 80430, 81690, 83370, 84210
Offset: 1
Keywords
Examples
46830 is in the sequence because it has 5 distinct prime factors (2, 3, 5, 7 and 223) and 223 > sqrt(46830).
Links
- Robert Israel, Table of n, a(n) for n = 1..10000
Programs
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Maple
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);