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%I #11 May 20 2017 10:48:13
%S 13860,16380,21420,23100,23940,25740,27300,28980,32340,33660,34650,
%T 35700,36036,36540,37620,38220,39060,39780,39900,40950,42900,44460,
%U 45540,46620,47124,48300,48510,49980,50820,51660,52668,53550,53820,54180
%N Numbers with prime factorization pqrs^2t^2.
%H T. D. Noe, <a href="/A189989/b189989.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]]=={1,1,1,2,2}; Select[Range[200000],f]
%o (PARI) list(lim)=my(v=List(),t1,t2,t3,t4); forprime(p=2,sqrtint(lim\420), t1=p^2; forprime(q=2,sqrtint(lim\(30*t1)), if(q==p, next); t2=q^2*t1; forprime(r=2,lim\(6*t2), if(r==p || r==q, next); t3=r*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. A179700, A189984, A189985.
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, May 03 2011
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