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A190319
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Numbers with prime factorization pq^2r^2s^4.
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3
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25200, 35280, 39600, 46800, 56700, 58800, 61200, 68400, 77616, 79380, 82800, 87120, 89100, 91728, 104400, 105300, 111600, 119952, 121680, 121968, 133200, 134064, 137700, 145200, 147600, 153900, 154800, 157500, 162288, 169200, 170352
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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, 2, 2, 4}; Select[Range[250000], f]
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PROG
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(PARI) list(lim)=my(v=List(), t1, t2, t3); forprime(p=2, sqrtnint(lim\180, 4), t1=p^4; forprime(q=2, sqrtint(lim\(12*t1)), if(q==p, next); t2=q^2*t1; forprime(r=2, sqrtint(lim\(2*t2)), if(r==p || r==q, next); t3=r^2*t2; forprime(s=2, lim\t3, if(s==p || s==q || s==r, next); listput(v, t3*s))))); 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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