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%I #16 Feb 21 2024 01:48:00
%S 720,1008,1200,1584,1620,1872,2268,2352,2448,2736,2800,3312,3564,3920,
%T 4050,4176,4212,4400,4464,5200,5328,5508,5808,5904,6156,6192,6768,
%U 6800,7452,7500,7600,7632,7938,8112,8496,8624,8784,9200,9396,9648,9680,10044
%N Products of form p^4*q^2*r where p, q and r are three distinct primes.
%H T. D. Noe, <a href="/A179669/b179669.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]]=={1,2,4}; Select[Range[10000], f]
%o (PARI) list(lim)=my(v=List(),t1,t2);forprime(p=2, (lim\12)^(1/4), t1=p^4;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
%Y Cf. A137493.
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Jul 23 2010
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