A107195 Primes of the form 7x^2 + 12y^2.
7, 19, 199, 223, 283, 307, 367, 439, 607, 643, 859, 1039, 1231, 1279, 1291, 1459, 1483, 1543, 1627, 1951, 2131, 2203, 2371, 2383, 2539, 2707, 2719, 2791, 3079, 3499, 3547, 3643, 3727, 3919, 4003, 4051, 4231, 4339, 4423, 4483, 4507, 4567
Offset: 1
Links
- Vincenzo Librandi and Ray Chandler, Table of n, a(n) for n = 1..10000 [First 1000 terms from Vincenzo Librandi]
- N. J. A. Sloane et al., Binary Quadratic Forms and OEIS (Index to related sequences, programs, references)
Programs
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Mathematica
QuadPrimes2[7, 0, 12, 10000] (* see A106856 *)
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PARI
list(lim)=my(v=List(),w,t); for(x=1, sqrtint(lim\7), w=7*x^2; for(y=0, sqrtint((lim-w)\12), if(isprime(t=w+12*y^2), listput(v,t)))); Set(v) \\ Charles R Greathouse IV, Feb 10 2017
Comments