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A064712
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Numbers k such that k^2 - prime(k) is a prime.
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9
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6, 10, 12, 18, 24, 28, 30, 40, 42, 48, 60, 76, 96, 104, 108, 114, 138, 146, 160, 166, 174, 176, 186, 190, 196, 198, 208, 230, 250, 258, 262, 270, 292, 296, 318, 320, 334, 336, 348, 356, 358, 362, 370, 372, 376, 382, 400, 420, 444, 454, 462, 472, 488, 494, 504
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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6 is in the sequence because 6^2 - prime(6) = 36 - 13 = 23 is a prime.
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MATHEMATICA
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Select[ Range[ 6, 1000, 2 ], PrimeQ[ #^2 - Prime[ # ] ] & ]
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PROG
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(PARI) n=0; forstep (m=6, 10^9, 2, if (isprime(m^2 - prime(m)), write("b064712.txt", n++, " ", m); if (n==1000, break)) ) \\ Harry J. Smith, Sep 23 2009
(Magma) [n: n in [6..1000] | IsPrime(n^2-NthPrime(n))]; // Vincenzo Librandi, Apr 14 2011
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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