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 A035072 #11 Oct 10 2019 03:59:38
%S A035072 23,71,224,708,2237,7072,22361,70711,223607,707107,2236068,7071068,
%T A035072 22360680,70710679,223606798,707106782,2236067978,7071067812,
%U A035072 22360679775,70710678119,223606797750,707106781187,2236067977500
%N A035072 a(n) is root of square starting with digit 5: first term of runs.
%F A035072 a(n) = ceiling(sqrt(5*10^n)), n > 1.
%t A035072 Table[Ceiling @ Sqrt[5 * 10^n], {n, 2 , 24}] (* _Amiram Eldar_, Oct 08 2019 *)
%Y A035072 Cf. A067475 (squares), A035076 (2..9).
%K A035072 nonn,base
%O A035072 2,1
%A A035072 _Patrick De Geest_, Nov 15 1998