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A139830
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Primes of the form 7x^2+6xy+7y^2.
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2
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7, 23, 47, 103, 127, 167, 223, 263, 367, 383, 463, 487, 503, 607, 647, 727, 743, 823, 863, 887, 967, 983, 1063, 1087, 1103, 1223, 1303, 1327, 1367, 1423, 1447, 1487, 1543, 1567, 1583, 1607, 1663, 1783, 1823, 1847, 2063, 2087, 2143, 2207, 2287
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OFFSET
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1,1
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COMMENTS
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Discriminant=-160. See A139827 for more information.
Also primes of the forms 7x^2+2xy+23y^2 and 7x^2+4xy+12y^2. See A140633. - T. D. Noe, May 19 2008
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LINKS
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FORMULA
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The primes are congruent to {7, 23} (mod 40).
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MATHEMATICA
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Union[QuadPrimes2[7, 6, 7, 10000], QuadPrimes2[7, -6, 7, 10000]] (* see A106856 *)
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PROG
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(Magma) [ p: p in PrimesUpTo(3000) | p mod 40 in {7, 23}]; // Vincenzo Librandi, Jul 29 2012
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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