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A046389 Products of exactly three distinct odd primes. 13
105, 165, 195, 231, 255, 273, 285, 345, 357, 385, 399, 429, 435, 455, 465, 483, 555, 561, 595, 609, 615, 627, 645, 651, 663, 665, 705, 715, 741, 759, 777, 795, 805, 861, 885, 897, 903, 915, 935, 957, 969, 987, 1001, 1005, 1015, 1023, 1045, 1065, 1085 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The old name was "Odd numbers with exactly 3 distinct prime factors", which is slightly ambiguous, since it might be interpreted to include 315 = 3^2*5*7. Cf. A278569. - N. J. A. Sloane, Nov 27 2016

LINKS

T. D. Noe, Table of n, a(n) for n=1..1000

MATHEMATICA

f[n_] := OddQ[n] && Last/@FactorInteger[n]=={1, 1, 1}; lst={}; Do[If[f[n], AppendTo[lst, n]], {n, 2000}]; lst (* Vladimir Joseph Stephan Orlovsky, Nov 23 2009 *)

PROG

(PARI) list(lim)=my(v=List(), t); forprime(p=3, lim^(1/3), forprime(q=p+1, sqrt(lim\p), t=p*q; forprime(r=q+1, lim\t, listput(v, t*r)))); vecsort(Vec(v)) \\ Charles R Greathouse IV, Jul 26 2011

CROSSREFS

Cf. A046316, A046405, A007304, A278569.

Sequence in context: A013590 A216918 A278569 * A154430 A118678 A152940

Adjacent sequences:  A046386 A046387 A046388 * A046390 A046391 A046392

KEYWORD

nonn

AUTHOR

Patrick De Geest, Jun 15 1998

EXTENSIONS

Name clarified by N. J. A. Sloane, Nov 27 2016

STATUS

approved

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Last modified January 22 05:11 EST 2019. Contains 319353 sequences. (Running on oeis4.)