login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A139666 Primes of the form x^2 + 1320*y^2. 2
1321, 1489, 1609, 2161, 2281, 2689, 3001, 3169, 3529, 4129, 4801, 5281, 5449, 5569, 5641, 6121, 6361, 6961, 7129, 7489, 7561, 7681, 8089, 8209, 8761, 9001, 9241, 9601, 9769, 10321, 10729, 12049, 12241, 12409, 12721, 12841, 13249, 13729 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Discriminant = -5280. See A139643 for more information.

The primes are congruent to {1, 49, 169, 289, 361, 529, 841, 889, 961, 1081} (mod 1320).

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, 1320, 10000] (* see A106856 *)

PROG

(MAGMA) [ p: p in PrimesUpTo(15000) | p mod 1320 in {1, 49, 169, 289, 361, 529, 841, 889, 961, 1081}]; // Vincenzo Librandi, Jul 29 2012

(MAGMA) k:=1320; [p: p in PrimesUpTo(14000) | NormEquation(k, p) eq true]; // Bruno Berselli, Jun 01 2016

CROSSREFS

Sequence in context: A295449 A092088 A068302 * A186469 A145754 A020403

Adjacent sequences:  A139663 A139664 A139665 * A139667 A139668 A139669

KEYWORD

nonn,easy

AUTHOR

T. D. Noe, Apr 29 2008

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified August 24 18:12 EDT 2019. Contains 326295 sequences. (Running on oeis4.)