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A137044
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Numbers k such that k and k^2 use only the digits 1, 3, 8 and 9.
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0
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OFFSET
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1,2
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COMMENTS
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Generated with DrScheme.
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LINKS
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EXAMPLE
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1998333891^2 = 3993338339919199881.
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MATHEMATICA
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With[{c={1, 3, 8, 9}}, Select[Flatten[Table[FromDigits/@Tuples[c, n], {n, 10}]], SubsetQ[c, IntegerDigits[#^2]]&]] (* Harvey P. Dale, Dec 04 2018 *)
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008
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STATUS
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approved
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