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A177425
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Integers with multiple and strictly distinct powers.
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4
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12, 18, 20, 24, 28, 40, 44, 45, 48, 50, 52, 54, 56, 63, 68, 72, 75, 76, 80, 88, 92, 96, 98, 99, 104, 108, 112, 116, 117, 124, 135, 136, 144, 147, 148, 152, 153, 160, 162, 164, 171, 172, 175, 176, 184, 188, 189, 192, 200, 207, 208, 212, 224, 232, 236, 242, 244, 245
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OFFSET
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1,1
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COMMENTS
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12=2^2*3, 18=2*3^2,.. 600=2^3*3*5^2,..
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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]]; lst={}; Do[If[Length[f[n]]>1&&f[n]==Union@f[n], AppendTo[lst, n]], {n, 0, 6!}]; lst
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PROG
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CROSSREFS
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Apart from its first term, A001749 is a subsequence.
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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