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A246043
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Biprimatic permutable numbers: Decimal numbers whose digits can be arranged to form exactly two prime numbers. No leading zeros.
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5
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13, 17, 31, 37, 71, 73, 79, 97, 107, 118, 119, 124, 125, 127, 128, 133, 139, 142, 146, 152, 164, 169, 170, 172, 181, 182, 191, 193, 196, 214, 215, 217, 218, 238, 239, 241, 251, 271, 277, 281, 283, 293, 313, 319, 328, 329, 331, 346, 347, 349, 356, 364, 365, 367, 368, 374, 376, 382, 386, 391, 392, 394, 412, 416, 421, 436, 437
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OFFSET
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1,1
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COMMENTS
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In base ten these numbers can be said to have a prime twin made up of the same digits.
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LINKS
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EXAMPLE
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170 -> 017 (forbidden), 071 (forbidden), 107 (prime), 170 (even), 701 (prime), 710 (even) -> conclusion: Two primes numbers.
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MATHEMATICA
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Select[Range[500], Count[FromDigits/@Select[Permutations[IntegerDigits[#]], #[[1]] != 0&], _?PrimeQ]==2&] (* Harvey P. Dale, Oct 23 2018 *)
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CROSSREFS
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A245808: Monoprimatic permutable numbers
A246044: Monoprimatic permutable primes
A246045: Biprimatic permutable primes
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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