The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A107145 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A107145

Primes of the form x^2 + 40y^2.
(history; published version)

#22 by Charles R Greathouse IV at Thu Sep 08 08:45:18 EDT 2022

PROG

(MAGMAMagma) [ p: p in PrimesUpTo(3000) | p mod 40 in {1, 9} ]; // Vincenzo Librandi, Jul 24 2012

Discussion

Thu Sep 08

08:45

OEIS Server: https://oeis.org/edit/global/2944

#21 by Charles R Greathouse IV at Thu Feb 09 14:39:20 EST 2017

STATUS

editing

approved

#20 by Charles R Greathouse IV at Thu Feb 09 14:39:18 EST 2017

NAME

Primes of the form x^2 + 40y^2.

COMMENTS

Discriminant = -160. See A107132 for more information.

PROG

(PARI) list(lim)=my(v=List(), t); forprime(p=41, lim, t=p%40; if(t==1||t==9, listput(v, p))); Vec(v) \\ Charles R Greathouse IV, Feb 09 2017

STATUS

approved

editing

#19 by OEIS Server at Sat Aug 09 09:33:42 EDT 2014

LINKS

Vincenzo Librandi and Ray Chandler, <a href="/A107145/b107145_1.txt">Table of n, a(n) for n = 1..10000</a> [First 1000 terms from Vincenzo Librandi]

#18 by Ray Chandler at Sat Aug 09 09:33:42 EDT 2014

STATUS

editing

approved

Discussion

Sat Aug 09

09:33

OEIS Server: Installed new b-file as b107145.txt.  Old b-file is now b107145_1.txt.

#17 by Ray Chandler at Sat Aug 09 09:33:36 EDT 2014

LINKS

N. J. A. Sloane et al., <a href="https://oeis.org/wiki/Binary_Quadratic_Forms_and_OEIS">Binary Quadratic Forms and OEIS</a> (Index to related sequences, programs, references)

#16 by Ray Chandler at Sat Aug 09 09:33:15 EDT 2014

LINKS

Vincenzo Librandi, <a href="/A107145/b107145.txt">Table of n, a(n) for n = 1..1000</a>

Vincenzo Librandi and Ray Chandler, <a href="/A107145/b107145_1.txt">Table of n, a(n) for n = 1..10000</a> [First 1000 terms from Vincenzo Librandi]

STATUS

approved

editing

#15 by N. J. A. Sloane at Tue Aug 05 14:15:33 EDT 2014

MATHEMATICA

QuadPrimesQuadPrimes2[1, 0, 40, 10000] (* see A106856 *)

Discussion

Tue Aug 05

14:15

OEIS Server: https://oeis.org/edit/global/2284

#14 by N. J. A. Sloane at Tue Aug 05 14:12:11 EDT 2014

MATHEMATICA

QuadPrimes[1, 0, 40, 10000] (* see A106856 *) Note: the original QuadPrimes had a bug which could sometimes give wrong answers. This sequence should be checked (unless the coefficient of xy in the quadratic form is zero, in which case QuadPrimes gives correct answers). - N. J. A. Sloane, Jun 04 2014

QuadPrimes[1, 0, 40, 10000] (* see A106856 *)

Discussion

Tue Aug 05

14:12

OEIS Server: https://oeis.org/edit/global/2282

#13 by N. J. A. Sloane at Mon Jun 16 11:28:42 EDT 2014

MATHEMATICA

Discussion

Mon Jun 16

11:28

OEIS Server: https://oeis.org/edit/global/2234