The OEIS is supported by the many generous donors to the OEIS Foundation.

 Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”). Other ways to Give
 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A139865 Primes of the form 7x^2 + 19y^2. 1
 7, 19, 47, 83, 131, 139, 199, 251, 271, 283, 311, 367, 419, 467, 479, 503, 587, 619, 643, 647, 691, 719, 727, 859, 1151, 1223, 1259, 1279, 1483, 1487, 1531, 1543, 1559, 1567, 1783, 1811, 1847, 1867, 1879, 1907, 1987, 2063, 2099, 2239, 2243, 2267 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Discriminant=-532. See A139827 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) FORMULA The primes are congruent to {7, 19, 47, 55, 83, 87, 111, 115, 131, 139, 159, 187, 195, 199, 215, 251, 271, 283, 311, 327, 339, 367, 391, 419, 423, 467, 479, 495, 503} (mod 532). MATHEMATICA QuadPrimes2[7, 0, 19, 10000] (* see A106856 *) PROG (Magma) [ p: p in PrimesUpTo(3000) | p mod 532 in {7, 19, 47, 55, 83, 87, 111, 115, 131, 139, 159, 187, 195, 199, 215, 251, 271, 283, 311, 327, 339, 367, 391, 419, 423, 467, 479, 495, 503}]; // Vincenzo Librandi, Jul 29 2012 (PARI) list(lim)=my(v=List(), w, t); for(x=0, sqrtint(lim\7), w=7*x^2; for(y=0, sqrtint((lim-w)\19), if(isprime(t=w+19*y^2), listput(v, t)))); Set(v) \\ Charles R Greathouse IV, Mar 07 2017 CROSSREFS Sequence in context: A278403 A143128 A238730 * A146403 A000491 A097039 Adjacent sequences: A139862 A139863 A139864 * A139866 A139867 A139868 KEYWORD nonn,easy AUTHOR T. D. Noe, May 02 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 | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified November 28 05:56 EST 2022. Contains 358407 sequences. (Running on oeis4.)