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 A083603 #15 Feb 16 2025 08:32:49
%S A083603 32788,120459,141899,255945,255946,266894,365783,378301,663429,707038,
%T A083603 740956,802226,821500,969110,973525,973670,1084126,1189427,1247619,
%U A083603 1295214,1312579,1672127,1876791,2003018,2030728,2136234,2170463
%N A083603 Starting positions of strings of five 1's in the decimal expansion of Pi.
%H A083603 <a href="/index/Ph#Pi314">Index entries for sequences related to the number Pi</a>
%H A083603 Dave Andersen, <a href="http://www.angio.net/pi/piquery">Pi-Search Page</a>
%H A083603 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PiDigits.html">Pi Digits.</a>
%t A083603 $MaxPrecision=10^8;a=RealDigits[Pi,10,4*9! ];lst={};Do[b=a[[1]][[n]];c=a[[1]][[n+1]];d=a[[1]][[n+2]];e=a[[1]][[n+3]];f=a[[1]][[n+4]];If[b==1&&c==1&&d==1&&e==1&&f==1,AppendTo[lst,n-1]],{n,3*7!,4*9!-4}];lst (* _Vladimir Joseph Stephan Orlovsky_, Jun 07 2009 *)
%Y A083603 Cf. A083602 (four 1's), A083604 (six 1's).
%K A083603 base,nonn
%O A083603 1,1
%A A083603 _Rick L. Shepherd_, May 01 2003