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A084669
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Primes which are a concatenation of prime(n) and n.
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8
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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
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OFFSET
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1,1
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LINKS
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EXAMPLE
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a(2)=239 because prime[9]=23 and concatenation of 23 and 9 is 239 which is prime.
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MATHEMATICA
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Select[Table[FromDigits[Flatten[{IntegerDigits[Prime[n]], IntegerDigits[n]}]], {n, 1, 500}], PrimeQ]
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PROG
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(Magma) [p: n in [1..500] | IsPrime(p) where p is Seqint(Intseq(n) cat Intseq(NthPrime(n)))]; // Bruno Berselli, Sep 15 2015
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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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STATUS
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approved
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