A106954 Primes of the form 4x^2+2xy+5y^2, with x and y any integer.

5, 7, 11, 17, 43, 47, 61, 73, 131, 137, 139, 149, 191, 199, 229, 233, 239, 251, 263, 277, 283, 311, 347, 349, 359, 389, 397, 443, 457, 461, 463, 467, 499, 541, 557, 577, 587, 613, 617, 631, 643, 647, 653, 691, 719, 727, 739, 757, 761, 769, 809, 821, 823

Offset: 1

Author

T. D. Noe, May 09 2005

Keywords

• nonn
• easy

Comments

Discriminant=-76.

Primes p such that the polynomial x^3-2x-2 is irreducible over Zp. The polynomial discriminant is also -76. - T. D. Noe, May 13 2005

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

Mathematica

Union[QuadPrimes2[4, 2, 5, 10000], QuadPrimes2[4, -2, 5, 10000]] (* see A106856 *)