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A107193
Primes of the form x^2 + 81y^2.
2
97, 181, 277, 337, 349, 373, 613, 733, 757, 829, 853, 1129, 1213, 1237, 1297, 1321, 1549, 1657, 1693, 1753, 2017, 2029, 2089, 2137, 2221, 2281, 2521, 2917, 3037, 3049, 3181, 3217, 3229, 3433, 3469, 3541, 3697, 3877, 4093, 4177, 4549, 4597
OFFSET
1,1
COMMENTS
Discriminant = -324. 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[1, 0, 81, 10000] (* see A106856 *)
PROG
(PARI) list(lim)=my(v=List(), w, t); for(x=1, sqrtint(lim\1), w=x^2; for(y=1, sqrtint((lim-w)\81), if(isprime(t=w+81*y^2), listput(v, t)))); Set(v) \\ Charles R Greathouse IV, Feb 10 2017
CROSSREFS
Sequence in context: A142094 A142212 A108655 * A256775 A364321 A142398
KEYWORD
nonn,easy
AUTHOR
T. D. Noe, May 13 2005
STATUS
approved