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 A253245 Primes that are the concatenation of prime(n) and prime(n+2). 1
 37, 1117, 1319, 1723, 4759, 89101, 97103, 101107, 113131, 151163, 181193, 223229, 227233, 239251, 251263, 293311, 313331, 337349, 389401, 421433, 461467, 491503, 587599, 631643, 647659, 683701, 691709, 701719, 739751, 761773, 809821 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Harvey P. Dale, Table of n, a(n) for n = 1..1000 MATHEMATICA Module[{nn=300, pr}, pr={#[[1]], #[[3]]}&/@Partition[Prime[Range[nn]], 3, 1]; Select[Table[FromDigits[Flatten[IntegerDigits/@pr[[n]]]], {n, Length[ pr]}], PrimeQ]] (* Harvey P. Dale, Nov 29 2015 *) PROG (PARI) for(n=1, 1e3, if(isprime(k=eval(Str(prime(n), prime(n+2)))), print1(k", "))) CROSSREFS Cf. A000040, A030461. Sequence in context: A217454 A101631 A005390 * A168166 A168165 A340539 Adjacent sequences: A253242 A253243 A253244 * A253246 A253247 A253248 KEYWORD nonn,easy,base AUTHOR Altug Alkan, Aug 22 2015 STATUS approved

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Last modified March 28 23:19 EDT 2023. Contains 361596 sequences. (Running on oeis4.)