A083631 Starting positions of strings of three 7's in the decimal expansion of Pi.

1589, 1590, 4575, 5241, 5242, 5322, 5323, 5355, 5450, 5863, 5864, 11298, 11733, 12661, 14292, 15501, 17234, 17502, 18516, 19903, 20404, 21423, 21571, 23538, 23749, 24373, 25551, 25788, 25858, 26796, 29504, 29505, 30988, 32478, 32479

Offset: 1

Author

Rick L. Shepherd, May 04 2003

Keywords

• base
• nonn

Comments

Position counted from and after decimal point. - Harvey P. Dale, Mar 13 2023

Links

• Index entries for sequences related to the number Pi
• Dave Andersen, Pi-Search Page
• Eric Weisstein's World of Mathematics, Pi Digits.

Crossrefs

Cf. A050254 (two 7's), A083632 (four 7's).

Programs

Mathematica

q=9!;z=7;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 *)
SequencePosition[RealDigits[Pi,10,33000][[1]],{7,7,7}][[;;,1]]-1 (* Harvey P. Dale, Mar 13 2023 *)