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A115960 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). 5
5338410, 5389230, 5403090, 5407710, 5421570, 5430810, 5444670, 5477010, 5490870, 5500110, 5504730, 5518590, 5527830, 5541690, 5569410, 5583270, 5597130, 5629470, 5638710, 5652570, 5680290, 5698770, 5712630, 5721870 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
5389230 is in the sequence because it has 6 distinct prime factors (2, 3, 5, 7, 11 and 2333) and 2333 > sqrt(5389230).
MAPLE
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);
MATHEMATICA
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 *)
CROSSREFS
Sequence in context: A058252 A147528 A338542 * A186014 A234496 A022258
KEYWORD
nonn
AUTHOR
Emeric Deutsch, Feb 02 2006
STATUS
approved

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Last modified April 14 17:14 EDT 2024. Contains 371666 sequences. (Running on oeis4.)