

A067885


Product of 6 distinct primes.


18



30030, 39270, 43890, 46410, 51870, 53130, 62790, 66990, 67830, 71610, 72930, 79170, 81510, 82110, 84630, 85470, 91770, 94710, 98670, 99330, 101010, 102102, 103530, 106590, 108570, 110670, 111930, 114114, 115710, 117390, 122430, 123690
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OFFSET

1,1


COMMENTS

Subsequence of A074969.  R. J. Mathar, Nov 24 2009


LINKS

T. D. Noe, Table of n, a(n) for n = 1..10000
Index to sequences related to prime signature


FORMULA

a(n) = n(log log n)^5/(120 log n).  Charles R Greathouse IV, Sep 14 2015


MATHEMATICA

f6Q[n_]:=Last/@FactorInteger[n]=={1, 1, 1, 1, 1, 1}; Select[Range[100000], f6Q] (* Vladimir Joseph Stephan Orlovsky, Aug 26 2008 *)
Select[Range[125000], PrimeNu[#]==PrimeOmega[#]==6&] (* Harvey P. Dale, May 14 2014 *)


PROG

(PARI) is(n)=factor(n)[, 2]==[1, 1, 1, 1, 1, 1]~ \\ Charles R Greathouse IV, Sep 14 2015
(PARI) is(n)=omega(n)==6 && bigomega(n)==6 \\ Hugo Pfoertner, Dec 18 2018


CROSSREFS

Cf. A006881, A007304, A046386, A046387, A067885, A123321, A123322, A115343 (product of 2, 3, 4,... distinct primes, respectively).
Sequence in context: A285655 A074969 A066765 * A285615 A258361 A072940
Adjacent sequences: A067882 A067883 A067884 * A067886 A067887 A067888


KEYWORD

nonn


AUTHOR

Benoit Cloitre, Mar 02 2002


STATUS

approved



