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A177493
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Products of cubes of 2 or more distinct primes.
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1
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216, 1000, 2744, 3375, 9261, 10648, 17576, 27000, 35937, 39304, 42875, 54872, 59319, 74088, 97336, 132651, 166375, 185193, 195112, 238328, 274625, 287496, 328509, 343000, 405224, 456533, 474552, 551368, 614125, 636056, 658503, 753571, 804357, 830584, 857375
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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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EXAMPLE
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216 = 2^3 * 3^3.
9261 = 3^3 * 7^3.
27000 = 2^3 * 3^3 * 5^3.
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MATHEMATICA
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f1[n_]:=Length[Last/@FactorInteger[n]]; f2[n_]:=Union[Last/@FactorInteger[n]]; lst={}; Do[If[f1[n]>1&&f2[n]=={3}, AppendTo[lst, n]], {n, 0, 9!}]; lst
Reap[Do[{p, e}=Transpose[FactorInteger[n]]; If[Length[p]>1 && Union[e]=={3}, Sow[n]], {n, 343000}]][[2, 1]]
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PROG
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(PARI) [k^3 | k<-[1..100], k>1 && !isprime(k) && issquarefree(k)] \\ Andrew Howroyd, Jan 14 2020
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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