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A163569 Numbers of the form p^3*q^2*r where p, q and r are three distinct primes. 4
360, 504, 540, 600, 756, 792, 936, 1176, 1188, 1224, 1350, 1368, 1400, 1404, 1500, 1656, 1836, 1960, 2052, 2088, 2200, 2232, 2250, 2484, 2600, 2646, 2664, 2904, 2952, 3096, 3132, 3348, 3384, 3400, 3500, 3800, 3816, 3996, 4056, 4116, 4248, 4312, 4392 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

There is no constraint on which of the three primes is the largest or smallest.

Subsequence of A137487. - R. J. Mathar, Aug 01 2009

LINKS

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

Index to sequences related to prime signature

EXAMPLE

360=2^3*3^2*5. 504=2^3*3^2*7. 1188=2^2*3^3*11.

MATHEMATICA

f[n_]:=Sort[Last/@FactorInteger[n]]=={1, 2, 3}; Select[Range[5000], f]

PROG

(PARI) list(lim)=my(v=List(), t1, t2); forprime(p=2, (lim\12)^(1/3), t1=p^3; forprime(q=2, sqrt(lim\t1), if(p==q, next); t2=t1*q^2; forprime(r=2, lim\t2, if(p==r||q==r, next); listput(v, t2*r)))); vecsort(Vec(v)) \\ Charles R Greathouse IV, Jul 20 2011

CROSSREFS

Sequence in context: A069478 A060665 A072414 * A063067 A076205 A048978

Adjacent sequences:  A163566 A163567 A163568 * A163570 A163571 A163572

KEYWORD

nonn,changed

AUTHOR

Vladimir Joseph Stephan Orlovsky, Jul 31 2009

STATUS

approved

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Last modified May 29 21:28 EDT 2017. Contains 287257 sequences.