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A140632 Primes of the form 55x^2+10xy+199y^2. 2
199, 439, 1039, 1231, 1951, 2239, 2551, 2791, 3559, 3631, 4759, 5431, 6991, 7159, 7591, 8839, 9439, 10111, 11119, 11311, 11959, 13159, 13711, 13831, 14479, 14551, 15391, 15679, 15991, 16519, 16831, 17239, 17359, 17839, 17911, 18199, 18919 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Discriminant=-43680. Also primes of the form 159x^2+120xy+160y^2.

In base 12, the sequence is 147, 307, 727, 867, 1167, 1367, 1587, 1747, 2087, 2127, 2907, 3187, 4067, 4187, 4487, 5147, 5567, 5X27, 6527, 6667, 6E07, 7747, 7E27, 8007, 8467, 8507, 8XX7, 90X7, 9307, 9687, 98X7, 9E87, X067, X3X7, X447, X647, XE47, where X is 10 and E is 11. Moreover, the discriminant is -21340. - Walter Kehowski, Jun 01 2008

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[55, 10, 199, 10000], QuadPrimes2[55, -10, 199, 10000]] (* see A106856 *)

CROSSREFS

Cf. A140633.

Sequence in context: A227283 A269325 A227284 * A142814 A105975 A095995

Adjacent sequences:  A140629 A140630 A140631 * A140633 A140634 A140635

KEYWORD

nonn,easy

AUTHOR

T. D. Noe, May 19 2008

STATUS

approved

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Last modified December 8 17:01 EST 2021. Contains 349596 sequences. (Running on oeis4.)