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%I #10 Aug 25 2016 23:12:04
%S 4620,5460,6930,7140,7980,8190,8580,9660,10710,11220,11550,11970,
%T 12012,12180,12540,12870,13020,13260,13650,14490,14820,15180,15540,
%U 15708,16170,16830,17220,17556,17850,17940,18018,18060,18270,18564,18810,19110,19140,19380
%N Numbers with prime factorization pqrst^2.
%H T. D. Noe, <a href="/A189983/b189983.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]]=={1,1,1,1,2}; Select[Range[30000],f]
%o (PARI) list(lim)=my(v=List(),t1,t2,t3,t4); forprime(p=2,sqrtint(lim\210), t1=p^2; forprime(q=2,lim\(30*t1), if(q==p, next); t2=q*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. A178740, A179644, A179670.
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, May 03 2011
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