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%I #14 Mar 16 2024 11:19:17
%S 1080,1512,2376,2808,3000,3672,4104,4968,6264,6696,6750,7000,7992,
%T 8232,8856,9288,10152,11000,11448,12744,13000,13176,13720,14472,15336,
%U 15768,17000,17064,17928,18522,19000,19224,20952,21816,22248,23000,23112
%N Numbers of the form p^3*q^3*r where p, q, and r are prime.
%H T. D. Noe, <a href="/A179688/b179688.txt">Table of n, a(n) for n = 1..1000</a>
%H Will Nicholes, <a href="http://willnicholes.com/math/primesiglist.htm">Prime Signatures</a>
%H <a href="/index/Pri#prime_signature">Index to sequences related to prime signature</a>
%t f[n_]:=Sort[Last/@FactorInteger[n]]=={1,3,3}; Select[Range[20000], f]
%o (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
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Jul 24 2010