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A179688 Numbers of the form p^3*q^3*r where p, q, and r are prime. 8
1080, 1512, 2376, 2808, 3000, 3672, 4104, 4968, 6264, 6696, 6750, 7000, 7992, 8232, 8856, 9288, 10152, 11000, 11448, 12744, 13000, 13176, 13720, 14472, 15336, 15768, 17000, 17064, 17928, 18522, 19000, 19224, 20952, 21816, 22248, 23000, 23112 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

Will Nicholes, Prime Signatures

Index to sequences related to prime signature

MATHEMATICA

f[n_]:=Sort[Last/@FactorInteger[n]]=={1, 3, 3}; Select[Range[20000], f]

PROG

(PARI) list(lim)=my(v=List(), t1, t2); forprime(p=2, (lim\2)^(1/6), t1=p^3; forprime(q=p+1, (lim\t1)^(1/3), t2=t1*q^3; 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: A023085 A163562 A214621 * A159210 A250538 A281259

Adjacent sequences:  A179685 A179686 A179687 * A179689 A179690 A179691

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Jul 24 2010

STATUS

approved

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Last modified January 22 11:56 EST 2019. Contains 319363 sequences. (Running on oeis4.)