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%I M0494 N0179 #42 Sep 08 2022 08:44:30
%S 3,4,5,6,7,9,10,11,12,14,16,17,20,21,22,25,27,29,31,32,36,39,40,42,45,
%T 46,47,49,51,54,55,56,57,60,61,65,66,67,69,71,77,84,86,87,90,94,95,97,
%U 101,102,104,115,116,121,126,127,131,132,135,139,141,142,145,146,149
%N Numbers n such that n^2 - n - 1 is prime.
%D D. H. Lehmer, Guide to Tables in the Theory of Numbers. Bulletin No. 105, National Research Council, Washington, DC, 1941, p. 46.
%D L. Poletti, Tavole di Numeri Primi Entro Limiti Diversi e Tavole Affini, Milan, 1920, p. 249.
%D N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H Carmine Suriano, <a href="/A002328/b002328.txt">Table of n, a(n) for n = 1..60000</a>
%F a(n) = (A088502(n)+1)/2. - _Ray Chandler_
%F a(n) = A094210(n) + 2. - _R. J. Mathar_, Aug 08 2012
%t Select[Range[10^3], PrimeQ[#^2 - # - 1] &] (* _Vincenzo Librandi_, Mar 20 2014 *)
%o (Magma) [n: n in [1..300]|IsPrime(n^2-n-1)]; // _Vincenzo Librandi_, Nov 21 2010
%o (PARI) is(n)=isprime(n^2 - n - 1) \\ _Charles R Greathouse IV_, Apr 28 2015
%Y Cf. A002327, A088502, A110013.
%K nonn,easy
%O 1,1
%A _N. J. A. Sloane_
%E Extended by _Ray Chandler_, Sep 07 2005
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