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 A091515 Numbers n such that (2^n - 1)^2 - 2 = 4^n - 2^(n+1) - 1 is prime. 12
 2, 3, 4, 6, 7, 10, 12, 15, 18, 19, 21, 25, 27, 55, 129, 132, 159, 171, 175, 315, 324, 358, 393, 435, 786, 1459, 1707, 2923, 6462, 14289, 39012, 51637, 100224, 108127, 110953, 175749, 185580, 226749, 248949, 253987, 520363, 653490, 688042, 695631 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Steven Harvey, Carol and Kynea Primes M. Rodenkirch, Carol and Kynea Prime Search Eric Weisstein's World of Mathematics, Near-Square Prime Eric Weisstein's World of Mathematics, Integer Sequence Primes MATHEMATICA lst={}; Do[p=(2^n-1)^2-2; If[PrimeQ[p], AppendTo[lst, n]], {n, 7!}]; lst (* Vladimir Joseph Stephan Orlovsky, Jan 27 2009 *) PROG (PARI) is(n)=ispseudoprime((2^n - 1)^2 - 2) \\ Charles R Greathouse IV, Feb 19 2016 CROSSREFS Cf. A093112, A091516. Sequence in context: A049806 A158381 A163180 * A036405 A051424 A137606 Adjacent sequences:  A091512 A091513 A091514 * A091516 A091517 A091518 KEYWORD nonn,hard AUTHOR Eric W. Weisstein, Jan 17 2004 EXTENSIONS More terms from Pab Ter (pabrlos(AT)yahoo.com), May 25 2004 a(36)=175749 from Cletus Emmanuel (cemmanu(AT)yahoo.com), Oct 08 2004 a(37)=185580 from Cletus Emmanuel (cemmanu(AT)yahoo.com), Nov 03 2004 Edited by Ray Chandler, Nov 15 2004 a(38)=226749 from Steven Harvey, Jan 11 2005 and subsequently confirmed as next term a(39) from Eric W. Weisstein, Mar 31 2006 a(40) = 253987 from Cletus Emmanuel (cemmanu(AT)yahoo.com), May 03 2007 a(41) = 520363 from Eric W. Weisstein, Jun 08 2016 (computed by Mark Rodenkirch) a(42) = 653490 from Eric W. Weisstein, Jun 15 2016 (computed by Mark Rodenkirch) a(43) = 688042 from Mark Rodenkirch, Jul 05 2016 a(44) = 695631 from Mark Rodenkirch, Jul 16 2016 STATUS approved

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Last modified March 19 15:02 EDT 2019. Contains 321330 sequences. (Running on oeis4.)