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

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A106972 Primes of the form 5x^2+4xy+5y^2, with x and y any integer. 1
5, 17, 41, 89, 101, 173, 257, 269, 293, 353, 461, 509, 521, 593, 677, 761, 773, 797, 857, 881, 929, 941, 1013, 1049, 1097, 1109, 1181, 1193, 1217, 1277, 1301, 1361, 1433, 1553, 1601, 1613, 1637, 1697, 1721, 1889, 1949, 1973, 2141, 2273, 2309 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Discriminant=-84.
Primes = 5, 17, or 41 (mod 84).
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
Union[QuadPrimes2[5, 4, 5, 10000], QuadPrimes2[5, -4, 5, 10000]] (* see A106856 *)
CROSSREFS
Sequence in context: A097121 A007904 A139545 * A086499 A097123 A139562
KEYWORD
nonn,easy
AUTHOR
T. D. Noe, May 09 2005
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.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 25 05:18 EDT 2024. Contains 371964 sequences. (Running on oeis4.)