

A140620


Primes of the form 23x^2+4xy+68y^2.


2



23, 263, 503, 647, 887, 1223, 1583, 1823, 1847, 2063, 2207, 2447, 2687, 2903, 3407, 3527, 3623, 3767, 4007, 4463, 4703, 4943, 4967, 5087, 5303, 5807, 5903, 5927, 6263, 6863, 7127, 7487, 7583, 7823, 8087, 8423, 8447, 9623, 9767, 10007, 10247
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,1


COMMENTS

Discriminant=6240. Also primes of the form 23x^2+18xy+207y^2.
In base 12, the sequence is 1E, 19E, 35E, 45E, 61E, 85E, XEE, 107E, 109E, 123E, 133E, 14EE, 167E, 181E, 1E7E, 205E, 211E, 221E, 239E, 26EE, 287E, 2X3E, 2X5E, 2E3E, 309E, 343E, 34EE, 351E, 375E, 3E7E, 415E, 43EE, 447E, 463E, 481E, 4X5E, 4X7E, 569E, 579E, 595E, 5E1E, where X is 10 and E is 11. Moreover, the discriminant is 3740.  Walter Kehowski, Jun 01 2008


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

Union[QuadPrimes2[23, 4, 68, 10000], QuadPrimes2[23, 4, 68, 10000]] (* see A106856 *)


CROSSREFS

Cf. A140633.
Sequence in context: A022618 A042018 A125411 * A002681 A240876 A142220
Adjacent sequences: A140617 A140618 A140619 * A140621 A140622 A140623


KEYWORD

nonn,easy


AUTHOR

T. D. Noe, May 19 2008


STATUS

approved



