This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A162307 #21 Sep 08 2022 08:45:46 %S A162307 3,19,31,83,131,223,383,479,643,1279,1823,2131,2239,2579,2819,3331, %T A162307 4483,4639,6163,6719,7103,7699,8963,9631,9859,10559,11779,13331,14143, %U A162307 14419,15263,17939,19843,21503,22531,24659,25759,28031,29599,30803,35423 %N A162307 Primes of the form k*(k+2)/3 - 2, k > 0. %C A162307 Or: primes of the form k*(k+1)*(k+2)/(k+(k+1)+(k+2))-2. %C A162307 Generated by k=3, 7, 9, 15, 19, 25, 33, 37, 43, .... %C A162307 Primes p such that 3*p+7 is a square. - _Vincenzo Librandi_, Dec 05 2015 %C A162307 Primes of the forms 3*k^2 + 2*k - 2 and 3*k^2 + 4*k - 1. - _Robert Israel_, Nov 27 2017 %H A162307 Robert Israel, <a href="/A162307/b162307.txt">Table of n, a(n) for n = 1..10000</a> %e A162307 k=3 contributes a term because 3*(3+2)/3 - 2 = 3 = a(1) is prime. %p A162307 select(isprime, [seq(seq((3*j+i)*(3*j+i+2)/3-2, i=0..1),j=1..1000)]); # _Robert Israel_, Nov 27 2017 %t A162307 f[n_]:=(n*(n+1)*(n+2))/(n+(n+1)+(n+2))-2; lst={};Do[p=f[n];If[PrimeQ[p], AppendTo[lst,p]],{n,6!}];lst %t A162307 Select[Table[(k(k+2))/3-2,{k,350}],PrimeQ] (* _Harvey P. Dale_, May 10 2014 *) %o A162307 (Magma) [p: p in PrimesUpTo(45000) | IsSquare(3*p+7)]; // _Vincenzo Librandi_, Dec 05 2015 %o A162307 (PARI) forprime(p=2, 1e5, if(issquare(3*p+7), print1(p , ", "))) \\ _Altug Alkan_, Dec 05 2015 %K A162307 nonn,easy %O A162307 1,1 %A A162307 _Vladimir Joseph Stephan Orlovsky_, Jun 30 2009 %E A162307 Definition simplified by _R. J. Mathar_, Jul 02 2009