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A271653
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Primes of the form 2*prime(2k) - prime(k).
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1
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11, 31, 47, 61, 113, 127, 179, 241, 307, 419, 433, 449, 491, 853, 881, 1063, 1153, 1201, 1289, 1487, 1823, 1997, 2011, 2027, 2333, 2441, 2459, 2647, 2851, 2927, 3041, 3449, 3491, 3853, 4057, 4241, 4259, 4397, 4423, 4679, 4721, 5003, 5179, 5233, 5569, 5653, 5867, 6397, 6481, 6661
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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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For n=1, 2*prime(2*2)-prime(2) = 2*7-3 = 11 is prime when k=2.
For n=2, 2*prime(2*4)-prime(4) = 2*19-7 = 31 is prime when k=4.
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MAPLE
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MATHEMATICA
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Select[Table[2*Prime[2 k] - Prime[k], {k, 0, 100}], PrimeQ]
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PROG
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(PARI) lista(nn) = for(n=1, nn, if(isprime(p=2*prime(2*n)-prime(n)), print1(p, ", "))); \\ Altug Alkan, Apr 13 2016
(Magma) [a: n in [0..400] | IsPrime(a) where a is 2*NthPrime(2*n) - NthPrime(n)]; // Vincenzo Librandi, Apr 15 2016
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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