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 A090686 Primes of the form 6n^2 - 1. 13
 5, 23, 53, 149, 293, 383, 599, 863, 1013, 1733, 2399, 2903, 4373, 4703, 5399, 6143, 7349, 8663, 11093, 12149, 16223, 18149, 20183, 21599, 23063, 23813, 25349, 27743, 29399, 31973, 33749, 35573, 40343, 41333, 45413, 51893, 56453, 59999, 62423 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Subset of A007528. The values of n for which 6*n^2 - 1 is prime are 1, 2, 3, 5, 7, 8, 10, 12, 13, 17, 20, 22, 27, 28, 30, 32, 35, 38, 43, 45, 52, 55, 58, 60, 62, 63, 65, 68, 70, 73, 75, 77, 82, 83, 87, 93, 97, 100, ... - Jonathan Vos Post, Aug 27 2006 LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..5000 MATHEMATICA lst={}; Do[p=6*n^2-1; If[PrimeQ[p], AppendTo[lst, p]], {n, 0, 3*5!}]; lst (* Vladimir Joseph Stephan Orlovsky, Jan 27 2009 *) Select[Table[6n^2-1, {n, 0, 700}], PrimeQ] (* Vincenzo Librandi, Dec 05 2011 *) PROG (PARI) mx2pmp(n) = { for(x=1, n, y = 6*x^2-1; if(isprime(y), print1(y", ")) ) } (MAGMA) [a: n in [0..500] | IsPrime(a) where a is 6*n^2-1]; // Vincenzo Librandi, Dec 05 2011 CROSSREFS Cf. A000040, A007528, A090687. Sequence in context: A140811 A247657 A241099 * A082277 A289154 A155851 Adjacent sequences:  A090683 A090684 A090685 * A090687 A090688 A090689 KEYWORD easy,nonn AUTHOR Cino Hilliard, Dec 18 2003 EXTENSIONS Edited by N. J. A. Sloane at the suggestion of R. J. Mathar, Apr 14 2008 STATUS approved

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Last modified December 14 12:04 EST 2019. Contains 329979 sequences. (Running on oeis4.)