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 A032625 Primes that are concatenations of n with n + 2. 2
 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Or, primes which are the concatenation of two consecutive odd numbers. - Parthasarathy Nambi, Apr 11 2005 LINKS EXAMPLE The first term is 13 which is a prime and is the concatenation of 1 and 3 - the first two odd numbers. MATHEMATICA 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 *) CROSSREFS Cf. A032607, A032617. Sequence in context: A125323 A075584 A126481 * A120782 A032652 A236952 Adjacent sequences:  A032622 A032623 A032624 * A032626 A032627 A032628 KEYWORD nonn,base AUTHOR Patrick De Geest, May 15 1998 EXTENSIONS Edited by N. J. A. Sloane, May 21 2008 at the suggestion of R. J. Mathar STATUS approved

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Last modified September 26 21:46 EDT 2020. Contains 337377 sequences. (Running on oeis4.)