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 A084669 Primes which are a concatenation of prime(n) and n. 8
 53, 239, 6719, 7321, 15737, 30763, 38977, 41981, 44987, 587107, 661121, 751133, 1051177, 1229201, 1297211, 1303213, 1327217, 1823281, 1913293, 1999303, 2131321, 2179327, 2207329, 2239333, 2371351, 2689391, 2699393, 3067439 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE a(2)=239 because prime[9]=23 and concatenation of 23 and 9 is 239 which is prime. MATHEMATICA Select[Table[FromDigits[Flatten[{IntegerDigits[Prime[n]], IntegerDigits[n]}]], {n, 1, 500}], PrimeQ] PROG (MAGMA) [p: n in [1..500] | IsPrime(p) where p is Seqint(Intseq(n) cat Intseq(NthPrime(n)))]; // Bruno Berselli, Sep 15 2015 CROSSREFS Cf. A084667. Subsequence of primes of A075110. Sequence in context: A053652 A142316 A142026 * A256339 A142357 A142061 Adjacent sequences:  A084666 A084667 A084668 * A084670 A084671 A084672 KEYWORD nonn,base AUTHOR Zak Seidov, Jun 29 2003 STATUS approved

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Last modified January 21 03:58 EST 2022. Contains 350473 sequences. (Running on oeis4.)