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%I #28 Sep 08 2022 08:44:50
%S 4,8,10,14,20,26,32,34,40,44,46,58,64,68,80,86,88,92,98,110,112,118,
%T 124,128,136,140,142,146,164,172,190,194,202,206,208,218,220,250,254,
%U 266,268,296,298,304,310,320,322,326,328,332,340,350,356,362,370,416,418
%N Numbers k such that k^2 - 3 is prime.
%H Nathaniel Johnston, <a href="/A028873/b028873.txt">Table of n, a(n) for n = 1..10000</a>
%H P. De Geest, <a href="http://www.worldofnumbers.com/consemor.htm">Palindromic Quasipronics of the form n(n+x)</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Near-SquarePrime.html">Near-Square Prime</a>
%e 8^2 - 3 = 61 is prime, so 8 is in the sequence.
%t a[n_]:=n^x-y;lst={};x=2;y=3;Do[If[PrimeQ[a[n]],AppendTo[lst,n]],{n,0,6!}];lst (* _Vladimir Joseph Stephan Orlovsky_, Jan 03 2009 *)
%o (Magma) [n: n in [2..10000] |IsPrime(n^2-3)] // _Vincenzo Librandi_, Aug 05 2010
%o (PARI) is(n)=isprime(n^2-3) \\ _Charles R Greathouse IV_, Jul 02 2013
%K nonn,easy
%O 1,1
%A _Patrick De Geest_
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