A106972 - OEIS

A106972

Primes of the form 5x^2+4xy+5y^2, with x and y any integer.

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

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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

Adjacent sequences: A106969 A106970 A106971 * A106973 A106974 A106975

KEYWORD

nonn,easy

AUTHOR

T. D. Noe, May 09 2005

STATUS

approved