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%I #9 Aug 25 2016 23:09:13
%S 900900,1178100,1261260,1316700,1392300,1556100,1593900,1649340,
%T 1843380,1883700,1949220,1981980,2009700,2034900,2102100,2148300,
%U 2178540,2187900,2231460,2342340,2375100,2445300,2463300,2538900,2564100,2591820
%N Numbers with prime factorization pqrs^2t^2u^2.
%H T. D. Noe, <a href="/A190391/b190391.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]]=={1,1,1,2,2,2};Select[Range[3500000],f]
%o (PARI) list(lim)=my(v=List(),t1,t2,t3,t4,t5); forprime(p=2,sqrtint(lim\13860), t1=p^2; forprime(q=2,sqrtint(lim\(420*t1)), if(q==p, next); t2=q^2*t1; forprime(r=2,sqrtint(lim\(30*t2)), if(r==p || r==q, next); t3=r^2*t2; forprime(s=2,lim\(6*t3), if(s==p || s==q || s==r, next); t4=s*t3; forprime(t=2,lim\(2*t4), if(t==p || t==q || t==r || t==s, next); t5=t*t4; forprime(u=2,lim\t5, if(u==p || u==q || u==r || u==s || u==t, next); listput(v, t5*u))))))); Set(v) \\ _Charles R Greathouse IV_, Aug 25 2016
%Y Cf. A190388, A190390.
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, May 09 2011
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