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A190379
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Numbers with prime factorization pqr^2s^2t^2.
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2
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69300, 81900, 97020, 107100, 114660, 119700, 128700, 144900, 149940, 152460, 161700, 167580, 168300, 182700, 188100, 191100, 195300, 198900, 202860, 212940, 222300, 227700, 233100, 242550, 249900, 252252, 254100, 255780, 258300, 269100
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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f[n_]:=Sort[Last/@FactorInteger[n]]=={1, 1, 2, 2, 2}; Select[Range[600000], f]
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PROG
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(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
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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