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A179666
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Products of the 4th power of a prime and a distinct prime of power 3 (p^4*q^3).
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12
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432, 648, 2000, 5000, 5488, 10125, 16875, 19208, 21296, 27783, 35152, 64827, 78608, 107811, 109744, 117128, 177957, 194672, 214375, 228488, 300125, 390224, 395307, 397953, 476656, 555579, 668168, 771147, 810448, 831875
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OFFSET
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1,1
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LINKS
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FORMULA
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MATHEMATICA
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f[n_]:=Sort[Last/@FactorInteger[n]]=={3, 4}; Select[Range[10^6], f]
With[{nn=40}, Select[Flatten[{#[[1]]^4 #[[2]]^3, #[[1]]^3 #[[2]]^4}&/@ Subsets[ Prime[Range[nn]], {2}]]//Union, #<=16nn^3&]] (* Harvey P. Dale, Nov 15 2020 *)
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PROG
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(PARI) list(lim)=my(v=List(), t); forprime(p=2, (lim\8)^(1/4), t=p^4; forprime(q=2, (lim\t)^(1/3), if(p==q, next); listput(v, t*q^3))); vecsort(Vec(v)) \\ Charles R Greathouse IV, Jul 20 2011
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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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