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A217496
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Primes of the form 2*n^2 + 50*n + 23.
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10
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23, 131, 191, 911, 1223, 1451, 1571, 1823, 3323, 3671, 3851, 5651, 6323, 6791, 7523, 8291, 9371, 10223, 12671, 15731, 16091, 16823, 25931, 28751, 29723, 39191, 43223, 50591, 53831, 55823, 60611, 62723, 64151, 64871, 68531, 73823, 77723, 80111, 87491, 90023
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OFFSET
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1,1
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COMMENTS
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Conjecture: 2^a(n)-1 is not prime; in other words, these primes are included in A054723.
2*a(n)+579 is a square. - Vincenzo Librandi, Mar 04 2013
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LINKS
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Vincenzo Librandi, Table of n, a(n) for n = 1..3000
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MATHEMATICA
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Select[Table[2 n^2 + 50 n + 23, {n, 0, 500}], PrimeQ]
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PROG
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(Magma) [a: n in [0..200] | IsPrime(a) where a is 2*n^2 + 50*n + 23];
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CROSSREFS
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Cf. A054723, A176549, A217494.
Subsequence of A002145.
Sequence in context: A176822 A157146 A232827 * A141963 A157907 A039613
Adjacent sequences: A217493 A217494 A217495 * A217497 A217498 A217499
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KEYWORD
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nonn,easy
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AUTHOR
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Vincenzo Librandi, Oct 09 2012
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STATUS
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approved
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