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A039667
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Numbers k that together with their double and triple contain every digit from 1-9 exactly once.
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0
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OFFSET
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0,1
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REFERENCES
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D. Wells, Curious and interesting numbers, Penguin Books, p. 128.
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LINKS
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EXAMPLE
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k=327 -> 2k=654 -> 3k=981 and 327654981 is a 'nine-digit' number.
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MATHEMATICA
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pdnQ[n_]:=Sort[Flatten[IntegerDigits[{n, 2n, 3n}]]]==Range[9]; Select[Range[987], pdnQ] (* Harvey P. Dale, Jul 07 2012 *)
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CROSSREFS
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KEYWORD
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nonn,base,fini,full
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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