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 A024701 #19 Feb 18 2024 02:03:29
%S A024701 2,6,12,30,42,72,90,132,210,240,342,420,462,552,702,870,930,1122,1260,
%T A024701 1332,1560,1722,1980,2352,2550,2652,2862,2970,3192,4032,4290,4692,
%U A024701 4830,5550,5700,6162,6642,6972,7482,8010,8190,9120,9312,9702,9900,11130,12432,12882,13110
%N A024701 a(n) = (-1 + prime(n+1)^2)/4.
%t A024701 Table[(Prime[n]^2-1)/4,{n,2,50}] (* _Harvey P. Dale_, Feb 12 2019 *)
%Y A024701 Cf. A084921.
%K A024701 nonn,easy
%O A024701 1,1
%A A024701 _Clark Kimberling_