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Numbers with prime factorization pq^3r^5.
5

%I #14 May 13 2013 01:49:34

%S 4320,6048,9504,9720,11232,12000,13608,14688,16416,19872,21384,25056,

%T 25272,26784,28000,31968,32928,33048,35424,36936,37152,40608,44000,

%U 44712,45792,50976,52000,52704,54880,56376,57888,60264,60750,61344

%N Numbers with prime factorization pq^3r^5.

%H T. D. Noe, <a href="/A190011/b190011.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>

%t f[n_]:=Sort[Last/@FactorInteger[n]]=={1,3,5};Select[Range[180000],f]

%o (PARI) list(lim)=my(v=List(),t1,t2);forprime(p=2, (lim\24)^(1/5), t1=p^5;forprime(q=2, (lim\t1)^(1/3), if(p==q, next);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 24 2011

%Y Cf. A179665, A179703.

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, May 04 2011