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A048405
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Primes with consecutive digits that differ exactly by 8.
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12
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2, 3, 5, 7, 19, 191, 919, 919191919, 91919191919, 91919191919191919, 91919191919191919191919, 191919191919191919191919191919191
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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2 is a term since all its consecutive digits differ by 5 (there aren't any).
19 is a term because 1 and 9 differ by 8.
23 is not a term because its consecutive digits differ only by 1.
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MATHEMATICA
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Module[{nn=500, nine, one}, one=Select[Table[FromDigits[PadRight[{}, n, {1, 9}]], {n, nn}], PrimeQ]; nine=Select[Table[FromDigits[PadRight[{}, n, {9, 1}]], {n, nn}], PrimeQ]; Sort[Join[{2, 3, 5, 7}, nine, one]]] (* Harvey P. Dale, Jan 04 2023 *)
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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