A107161 Primes of the form 2x^2 + 27y^2.

2, 29, 59, 227, 251, 269, 293, 419, 443, 677, 683, 773, 821, 827, 1013, 1187, 1277, 1301, 1373, 1451, 1493, 1523, 1709, 1733, 1811, 1901, 1949, 2027, 2237, 2243, 2339, 2357, 2381, 2477, 2579, 2693, 2699, 2909, 3299, 3371, 3389, 3413, 3467

Offset

1,1

Comments

Discriminant = -216. See A107132 for more information.

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)

Mathematica

QuadPrimes2[2, 0, 27, 10000] (* see A106856 *)
With[{nn=50}, Take[Union[Select[2#[[1]]+27#[[2]]&/@(Tuples[Range[ 0, nn], 2]^2), PrimeQ]], nn]] (* Harvey P. Dale, Jun 15 2014 *)

Prog

(PARI) list(lim)=my(v=List(), w, t); for(x=1, sqrtint(lim\2), w=2*x^2; for(y=0, sqrtint((lim-w)\27), if(isprime(t=w+27*y^2), listput(v, t)))); Set(v) \\ Charles R Greathouse IV, Feb 09 2017

Crossrefs

Sequence in context: A281546 A115448 A276169 * A372932 A041097 A067071

Adjacent sequences: A107158 A107159 A107160 * A107162 A107163 A107164

Keyword

nonn,easy

Author

T. D. Noe, May 13 2005

Extensions

Terms, including b-file, checked by Harvey P. Dale, Jun 16 2014

Status

approved