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A032625
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Primes that are concatenations of n with n + 2.
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2
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13, 79, 911, 2729, 3739, 4547, 4951, 5153, 5557, 6163, 6971, 7577, 105107, 109111, 115117, 117119, 121123, 151153, 159161, 181183, 187189, 195197, 201203, 211213, 217219, 225227, 247249, 271273, 277279, 285287, 289291
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OFFSET
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1,1
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COMMENTS
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Or, primes which are the concatenation of two consecutive odd numbers. - Parthasarathy Nambi, Apr 11 2005
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LINKS
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EXAMPLE
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The first term is 13 which is a prime and is the concatenation of 1 and 3 - the first two odd numbers.
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MATHEMATICA
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lp = Range[1, 320, 2]; lst = {}; Do[p = FromDigits[ Join[ IntegerDigits[ lp[[n]]], IntegerDigits[ lp[[n + 1]] ]]]; If[ PrimeQ[p], AppendTo[lst, p]], {n, 159}]; lst (* Robert G. Wilson v, Apr 12 2005 *)
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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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