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A115960
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Numbers n having exactly 6 distinct prime factors, the largest of which is greater than or equal to sqrt(n) (i.e., sqrt(n)-rough numbers with exactly 6 distinct prime factors).
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5
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5338410, 5389230, 5403090, 5407710, 5421570, 5430810, 5444670, 5477010, 5490870, 5500110, 5504730, 5518590, 5527830, 5541690, 5569410, 5583270, 5597130, 5629470, 5638710, 5652570, 5680290, 5698770, 5712630, 5721870
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OFFSET
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1,1
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LINKS
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EXAMPLE
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5389230 is in the sequence because it has 6 distinct prime factors (2, 3, 5, 7, 11 and 2333) and 2333 > sqrt(5389230).
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MAPLE
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with(numtheory): a:=proc(n) if nops(factorset(n))=6 and factorset(n)[6]^2>=n then n else fi end: seq(a(n), n=(2*3*5*7*11)^2..5850000);
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MATHEMATICA
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dpf6Q[n_]:=Module[{pf=FactorInteger[n][[All, 1]]}, Length[pf]==6 && pf[[6]]>=Sqrt[n]]; Select[Range[6*10^6], dpf6Q] (* Harvey P. Dale, Mar 24 2017 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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