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%I #16 May 20 2017 10:48:51
%S 6300,8820,9900,11700,14700,15300,17100,19404,20700,21780,22050,22932,
%T 26100,27900,29988,30420,30492,33300,33516,36300,36900,38700,40572,
%U 42300,42588,47700,50700,51156,52020,53100,53900,54450,54684,54900
%N Numbers with prime factorization pq^2r^2s^2.
%H T. D. Noe, <a href="/A189344/b189344.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]]=={1,2,2,2}; Select[Range[90000],f]
%o (PARI) list(lim)=my(v=List(),t1,t2,t3); forprime(p=2,sqrtint(lim\180), t1=p^2; forprime(q=2,sqrtint(lim\(12*t1)), if(q==p, next); t2=q^2*t1; forprime(r=2,sqrtint(lim\(2*t2)), if(r==p || r==q, next); t3=r^2*t2; forprime(s=2,lim\t3, if(s==p || s==q || s==r, next); listput(v, t3*s))))); Set(v) \\ _Charles R Greathouse IV_, Aug 25 2016
%Y Cf. A179688, A179693, A179700.
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, May 09 2011
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