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A087593
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Define dd(n) = the number formed by concatenating the absolute difference of successive digits. Sequence contains primes p such that dd(p) is also prime. (Primes in which the number formed by successive digit difference is also a prime.).
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8
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13, 29, 31, 41, 47, 53, 61, 79, 83, 97, 101, 103, 107, 109, 113, 163, 227, 229, 241, 263, 269, 281, 307, 331, 347, 367, 401, 449, 463, 487, 503, 509, 521, 523, 541, 547, 557, 563, 569, 587, 601, 607, 641, 647, 661, 701, 709, 743, 769, 787, 809, 821, 823, 829
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OFFSET
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0,1
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COMMENTS
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Conjecture: Sequence is infinite. Subsidiary sequence: number of n-digit members.
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LINKS
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EXAMPLE
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29 is a member as absolute(2-9) = 7 is a prime.
101 is a member as 1~0= 1, 0~1 = 1 and dd(101) = 11 is a prime.
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MATHEMATICA
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Select[Prime[Range[200]], PrimeQ[FromDigits[Abs[Differences[ IntegerDigits[ #]]]]]&] (* Harvey P. Dale, Oct 10 2014 *)
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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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