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A090717
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Primes which are also prime if their base 64 representation is interpreted as a base 10 number.
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1
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2, 3, 5, 7, 67, 71, 73, 131, 137, 193, 199, 257, 263, 449, 457, 521, 4099, 4231, 4289, 4297, 4423, 4483, 4547, 4673, 4679, 8329, 8387, 8513, 8641, 8647, 8707, 12487, 12553, 12611, 12739, 12809, 16649, 16903, 20483, 20611, 20743, 20807, 20873
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OFFSET
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1,1
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LINKS
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EXAMPLE
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67 is prime; in base 64 it is written "13" and the base 10 number 13 is also prime.
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MATHEMATICA
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b64Q[n_]:= Module[{idn64=IntegerDigits[n, 64]}, Max[idn64]<10&&PrimeQ[FromDigits[idn64]]]; Select[Prime[Range[PrimePi[30000]]], b64Q] (* Vincenzo Librandi, Apr 18 2013 *)
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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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EXTENSIONS
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STATUS
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approved
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