A107163 Primes of the form 7x^2 + 8y^2.
7, 71, 79, 191, 263, 463, 599, 631, 823, 863, 919, 991, 1031, 1327, 1367, 1471, 1583, 1607, 1831, 1999, 2087, 2111, 2143, 2311, 2543, 2647, 2671, 2767, 2879, 2927, 3119, 3623, 3767, 3823, 4327, 4447, 4463, 4663, 4783, 4799, 4951, 5023, 5119
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, 8, 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)\8), if(isprime(t=w+8*y^2), listput(v,t)))); Set(v) \\ Charles R Greathouse IV, Feb 09 2017
Comments