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 A140614 Primes of the form 15x^2+12xy+20y^2. 2
 23, 47, 71, 191, 311, 383, 599, 647, 719, 839, 863, 911, 983, 1103, 1367, 1439, 1511, 1607, 1871, 2039, 2399, 2423, 2447, 2663, 2687, 2711, 2927, 3023, 3191, 3359, 3623, 3719, 3767, 4007, 4079, 4271, 4679, 4799, 4871, 4943, 5039, 5087, 5303 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Discriminant=-1056. Also primes of the form 23x^2+12xy+36y^2. In base 12 the sequence is 1E, 3E, 5E, 13E, 21E, 27E, 41E, 45E, 4EE, 59E, 5EE, 63E, 69E, 77E, 95E, 9EE, X5E, E1E, 10EE, 121E, 147E, 149E, 14EE, 165E, 167E, 169E, 183E, 18EE, 1X1E, 1E3E, 211E, 219E, 221E, 239E, 243E, 257E, 285E, 293E, 299E, 2X3E, 2XEE, 2E3E, 309E, where X is 10 and E is 11. Moreover, the discriminant is -740. - Walter Kehowski, May 31 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[15, 12, 20, 10000], QuadPrimes2[15, -12, 20, 10000]] (* see A106856 *) CROSSREFS Cf. A140633. Sequence in context: A183010 A134517 A141376 * A001124 A139501 A292509 Adjacent sequences:  A140611 A140612 A140613 * A140615 A140616 A140617 KEYWORD nonn,easy AUTHOR T. D. Noe, May 19 2008 STATUS approved

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Last modified May 16 11:20 EDT 2021. Contains 343942 sequences. (Running on oeis4.)