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A139502 Primes of the form x^2 + 22x*y + y^2 for x and y nonnegative. 5
241, 409, 601, 769, 1009, 1129, 1201, 1249, 1321, 1489, 1609, 1801, 2089, 2161, 2281, 2521, 2689, 3001, 3049, 3121, 3169, 3361, 3529, 3769, 3889, 4129, 4201, 4441, 4561, 4729, 4801, 4969, 5209, 5281, 5449, 5521, 5569, 5641, 5689, 5881, 6121, 6361, 6481 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Also primes of the form x^2 + 120y^2. - T. D. Noe, Apr 29 2008
Also primes of the form x^2+240y^2. See A140633. - T. D. Noe, May 19 2008
In base 12, the sequence is 181, 2X1, 421, 541, 701, 7X1, 841, 881, 921, X41, E21, 1061, 1261, 1301, 13X1, 1561, 1681, 18X1, 1921, 1981, 1X01, 1E41, 2061, 2221, 2301, 2481, 2521, 26X1, 2781, 28X1, 2941, 2X61, 3021, 3081, 31X1, 3241, 3281, 3321, 3361, 34X1, 3661, 3821, 3901, where X is 10 and E is 11. Moreover, the discriminant is 340. - Walter Kehowski, Jun 01 2008
LINKS
N. J. A. Sloane et al., Binary Quadratic Forms and OEIS (Index to related sequences, programs, references)
FORMULA
The primes are congruent to {1, 49} (mod 120). - T. D. Noe, Apr 29 2008
MATHEMATICA
QuadPrimes2[1, 0, 120, 10000] (* see A106856 *)
PROG
(Magma) [ p: p in PrimesUpTo(7000) | p mod 120 in {1, 49}]; // Vincenzo Librandi, Jul 28 2012
CROSSREFS
Cf. A139643.
Sequence in context: A153423 A050968 A142918 * A140629 A325088 A321582
KEYWORD
nonn,easy
AUTHOR
Artur Jasinski, Apr 24 2008
STATUS
approved

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Last modified April 23 07:57 EDT 2024. Contains 371905 sequences. (Running on oeis4.)