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 A045386 Primes congruent to {1, 2, 4} mod 7. 2
 2, 11, 23, 29, 37, 43, 53, 67, 71, 79, 107, 109, 113, 127, 137, 149, 151, 163, 179, 191, 193, 197, 211, 233, 239, 263, 277, 281, 317, 331, 337, 347, 359, 373, 379, 389, 401, 421, 431, 443, 449, 457, 463, 487, 491, 499, 541, 547, 557, 569, 571, 599, 613, 617, 631, 641, 653, 659, 673 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Rational primes that decompose in the field Q(sqrt(-7)). - N. J. A. Sloane, Dec 25 2017 All these primes can be represented by the binary quadratic form x^2 + xy + 2y^2. - Alonso del Arte, Jun 13 2014. Indeed, apart from the fact that 7 is missing, this appears to coincide with A045373. - N. J. A. Sloane, Jun 14 2014 REFERENCES Şaban Alaca & Kenneth S. Williams, Introductory Algebraic Number Theory. Cambridge: Cambridge University Press (2004) p. 48, Theorem 2.5.4. LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..1000 N. J. A. Sloane et al., Binary Quadratic Forms and OEIS (Index to related sequences, programs, references) MATHEMATICA Select[Prime[Range[300]], MemberQ[{1, 2, 4}, Mod[#, 7]] &] (* Vincenzo Librandi, Aug 11 2012 *) PROG (MAGMA) [p: p in PrimesUpTo(600) | p mod 7 in [1, 2, 4]]; // Vincenzo Librandi, Aug 11 2012 CROSSREFS Cf. A002144, A007645, A045373. Sequence in context: A004642 A185545 A001032 * A084354 A066725 A087340 Adjacent sequences:  A045383 A045384 A045385 * A045387 A045388 A045389 KEYWORD nonn,easy AUTHOR N. J. A. Sloane, Dec 11 1999 STATUS approved

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Last modified May 18 12:26 EDT 2021. Contains 343995 sequences. (Running on oeis4.)