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A107141
Primes of the form 4x^2 + 9y^2.
3
13, 73, 97, 109, 181, 229, 241, 277, 337, 409, 421, 457, 541, 709, 733, 757, 829, 1009, 1033, 1093, 1117, 1129, 1153, 1213, 1237, 1249, 1381, 1453, 1489, 1597, 1609, 1621, 1669, 1753, 1777, 1873, 2017, 2029, 2089, 2113, 2161, 2221, 2281
OFFSET
1,1
COMMENTS
Discriminant = -144. See A107132 for more information.
These appear to be the same as Glaisher's 1889 list of primes == 1 mod 12 that have "negative character". - N. J. A. Sloane, Jul 30 2015
REFERENCES
J. W. L. Glaisher, On the square of Euler's series, Proc. London Math. Soc., 21 (1889), 182-194.
LINKS
Vincenzo Librandi and Ray Chandler, Table of n, a(n) for n = 1..10000 [First 1000 terms from Vincenzo Librandi]
S. R. Finch, Powers of Euler's q-Series, (arXiv:math.NT/0701251).
N. J. A. Sloane et al., Binary Quadratic Forms and OEIS (Index to related sequences, programs, references)
MATHEMATICA
QuadPrimes2[4, 0, 9, 10000] (* see A106856 *)
PROG
(PARI) list(lim)=my(v=List(), w, t); for(x=1, sqrtint(lim\4), w=4*x^2; for(y=1, sqrtint((lim-w)\9), if(isprime(t=w+9*y^2), listput(v, t)))); Set(v) \\ Charles R Greathouse IV, Feb 09 2017
CROSSREFS
Sequence in context: A299192 A300028 A322478 * A139849 A139911 A097460
KEYWORD
nonn,easy
AUTHOR
T. D. Noe, May 13 2005
STATUS
approved