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A088069
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Cubes sandwiched between two numbers divisible by cubes.
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1
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4913, 6859, 166375, 704969, 2048383, 4173281, 7880599, 12649337, 15438249, 15813251, 19902511, 28372625, 34328125, 40353607, 53582633, 71473375, 90518849, 115501303, 141420761, 174676879, 208527857, 251239591, 294079625
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OFFSET
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0,1
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COMMENTS
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Sequence is infinite. If k is a member then so is k^3. Subsidiary sequence: fourth powers sandwiched between two numbers divisible by fourth powers.
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LINKS
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EXAMPLE
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4913= 17^3 is a member as 4912 is divisible by 8 and 4950 is divisible by 27.
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MATHEMATICA
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Select[Range[2, 1000], Last[Union[Transpose[FactorInteger[ #^3 - 1]][[2]]]] > 2 && Last[Union[Transpose[FactorInteger[ #^3 + 1]][[2]]]] > 2 &]^3 - Tanya Khovanova, Sep 08 2007
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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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