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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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified December 15 20:00 EST 2019. Contains 330000 sequences. (Running on oeis4.)