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A139856
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Primes of the form 5x^2 + 24y^2.
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2
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5, 29, 101, 149, 269, 389, 461, 509, 701, 821, 941, 1061, 1109, 1181, 1229, 1301, 1709, 1901, 1949, 2069, 2141, 2309, 2381, 2549, 2621, 2741, 2789, 2861, 2909, 3221, 3389, 3461, 3581, 3701, 3821, 3989, 4229, 4349, 4421, 5021, 5189, 5261
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OFFSET
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1,1
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COMMENTS
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Discriminant=-480. See A139827 for more information.
Except for 5, also primes of the form 21x^2+6xy+29y^2. See A140633. - T. D. Noe, May 19 2008
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LINKS
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FORMULA
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Except for 5, the primes are congruent to {29, 101} (mod 120).
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MATHEMATICA
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QuadPrimes2[5, 0, 24, 10000] (* see A106856 *)
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PROG
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(Magma) [5] cat [ p: p in PrimesUpTo(6000) | p mod 120 in {29, 101}]; // Vincenzo Librandi, Jul 29 2012
(PARI) list(lim)=my(v=List(), w, t); for(x=1, sqrtint(lim\5), w=5*x^2; for(y=0, sqrtint((lim-w)\24), if(isprime(t=w+24*y^2), listput(v, t)))); Set(v) \\ Charles R Greathouse IV, Feb 22 2017
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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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