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%I #11 May 20 2017 11:47:21
%S 69300,81900,97020,107100,114660,119700,128700,144900,149940,152460,
%T 161700,167580,168300,182700,188100,191100,195300,198900,202860,
%U 212940,222300,227700,233100,242550,249900,252252,254100,255780,258300,269100
%N Numbers with prime factorization pqr^2s^2t^2.
%H T. D. Noe, <a href="/A190379/b190379.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]]=={1,1,2,2,2};Select[Range[600000],f]
%o (PARI) list(lim)=my(v=List(),t1,t2,t3,t4); forprime(p=2,sqrtint(lim\1260), t1=p^2; forprime(q=2,sqrtint(lim\(60*t1)), if(q==p, next); t2=q^2*t1; forprime(r=2,sqrtint(lim\(6*t2)), if(r==p || r==q, next); t3=r^2*t2; forprime(s=2,lim\(2*t3), if(s==p || s==q || s==r, next); t4=s*t3; forprime(t=2,lim\t4, if(t==p || t==q || t==r || t==s, next); listput(v, t4*t)))))); Set(v) \\ _Charles R Greathouse IV_, Aug 25 2016
%Y Cf. A190110, A190111.
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, May 09 2011
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