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Starting positions of strings of six 1's in the decimal expansion of Pi.
3

%I #16 Jul 04 2018 12:41:13

%S 255945,2645268,3218870,4657555,4657556,5130874,5425806,5961931,

%T 6653783,9036112,11867965,13249047,13255651,15684440,18548887,

%U 20316848,22107705,22564362,23503699,28388441,28580580,29435972,30584158,31678241

%N Starting positions of strings of six 1's in the decimal expansion of Pi.

%H Dave Andersen, <a href="http://www.angio.net/pi/piquery">Pi-Search Page</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PiDigits.html">Pi Digits.</a>

%H <a href="/index/Ph#Pi314">Index entries for sequences related to the number Pi</a>

%t $MaxPrecision=10^8;a=RealDigits[Pi,10,8*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]];g=a[[1]][[n+5]];If[b==1&&c==1&&d==1&&e==1&&f==1&&g==1,AppendTo[lst,n-1]],{n,2*8!,8*9!-5}];lst (* _Vladimir Joseph Stephan Orlovsky_, Jun 07 2009 *)

%t SequencePosition[RealDigits[Pi,10,32*10^6][[1]],{1,1,1,1,1,1}][[All,1]]-1 (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jul 04 2018 *)

%Y Cf. A083603 (five 1's), A083605 (seven 1's).

%K base,nonn

%O 1,1

%A _Rick L. Shepherd_, May 01 2003