A107207 - OEIS

A107207

Primes of the form 7x^2 + 13y^2.

7, 13, 41, 59, 227, 229, 271, 353, 383, 461, 577, 619, 643, 773, 811, 839, 1021, 1307, 1399, 1489, 1601, 1627, 1697, 1753, 1783, 1867, 1879, 2273, 2281, 2309, 2579, 2593, 2719, 2897, 2917, 2953, 3037, 3323, 3359, 3373, 3391, 3671, 3853, 3911

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Discriminant = -364. 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[7, 0, 13, 10000] (* see A106856 *)

PROG

(PARI) list(lim)=my(v=List(), w, t); for(x=0, sqrtint(lim\7), w=7*x^2; for(y=0, sqrtint((lim-w)\13), if(isprime(t=w+13*y^2), listput(v, t)))); Set(v) \\ Charles R Greathouse IV, Feb 10 2017

CROSSREFS

Sequence in context: A123250 A062591 A056249 * A045464 A134854 A330671

Adjacent sequences: A107204 A107205 A107206 * A107208 A107209 A107210

KEYWORD

nonn,easy

AUTHOR

T. D. Noe, May 13 2005

STATUS

approved