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 A083625 #14 Feb 16 2025 08:32:49
%S A083625 2440,3151,4000,4435,5403,6840,10163,10335,10591,13594,15888,16109,
%T A083625 18504,20231,21880,21881,23057,23511,24566,25948,26212,27703,27841,
%U A083625 29666,29868,29869,32427,32428,33363,36353,38132,40370,40650,43523
%N A083625 Starting positions of strings of three 6's in the decimal expansion of Pi.
%H A083625 <a href="/index/Ph#Pi314">Index entries for sequences related to the number Pi</a>
%H A083625 Dave Andersen, <a href="http://www.angio.net/pi/piquery">Pi-Search Page</a>
%H A083625 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PiDigits.html">Pi Digits.</a>
%t A083625 q=9!;z=6;a=RealDigits[Pi,10,q];lst={};Do[b=a[[1]][[n]];c=a[[1]][[n+1]];d=a[[1]][[n+2]];If[b==z&&c==z&&d==z,AppendTo[lst,n-1]],{n,q-2}];lst (* _Vladimir Joseph Stephan Orlovsky_, Jun 19 2009 *)
%Y A083625 Cf. A050245 (two 6's), A083626 (four 6's).
%K A083625 base,nonn
%O A083625 1,1
%A A083625 _Rick L. Shepherd_, May 03 2003