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 A050208 #29 Feb 16 2025 08:32:40
%S A050208 94,153,154,174,362,395,427,437,445,494,709,758,846,921,983,984,1129,
%T A050208 1185,1349,1503,1534,1656,1849,1896,2458,2497,2724,2740,2779,2904,
%U A050208 3253,3398,3493,3503,3504,3534,3735,3822,3844,3847,3963,3992,3993
%N A050208 Starting positions of strings of 2 1's in the decimal expansion of Pi.
%H A050208 Amiram Eldar, <a href="/A050208/b050208.txt">Table of n, a(n) for n = 1..10000</a>
%H A050208 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PiDigits.html">Pi Digits</a>
%H A050208 <a href="/index/Ph#Pi314">Index entries for sequences related to the number Pi</a>
%t A050208 a=RealDigits[Pi,10,8! ];lst={};Do[b=a[[1]][[n]];c=a[[1]][[n+1]];If[b==1&&c==1,AppendTo[lst,n-1]],{n,8!-1}];lst (* _Vladimir Joseph Stephan Orlovsky_, Jun 02 2009 *)
%t A050208 Flatten[Position[Partition[RealDigits[Pi,10,4000][[1]],2,1],_?(#=={1,1}&) ]]-1 (* _Harvey P. Dale_, Dec 01 2013 *)
%t A050208 SequencePosition[RealDigits[Pi,10,4000][[1]],{1,1}][[;;,1]]-1 (* _Harvey P. Dale_, Jul 08 2024 *)
%Y A050208 Cf. A037008, A037000, A037001, A037002, A037003, A037004, A037005, A036974, A037006, A037007, A014777, A134212, A134213, A134214, A134215, A134216, A134217, A134218, A134218, A134219.
%K A050208 nonn,base
%O A050208 1,1
%A A050208 _Eric W. Weisstein_
%E A050208 Edited by _N. J. A. Sloane_, Aug 10 2010