A083643 Starting positions of strings of four 9's in the decimal expansion of Pi.

762, 763, 764, 17988, 19437, 19446, 19447, 22753, 31900, 42095, 56988, 56989, 81293, 120564, 140953, 161862, 161863, 177122, 182604, 191104, 193034, 193035, 193036, 204198, 210140, 211794, 220507, 220568, 220569, 224317, 235425, 235775

Offset: 1

Author

Rick L. Shepherd, May 05 2003

Keywords

• base
• nonn

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..1000
• Index entries for sequences related to the number Pi
• Dave Andersen, Pi-Search Page
• Eric Weisstein's World of Mathematics, Pi Digits.

Crossrefs

Cf. A083642 (three 9's), A083644 (five 9's).

Programs

Mathematica

Transpose[StringPosition[StringDrop[ToString[N[Pi,9! ]],2],"9999"]][[1]] (* Vladimir Joseph Stephan Orlovsky, Jun 19 2009 *)
Module[{digs=240000,p},p=RealDigits[Pi,10,digs][[1]];SequencePosition[p,{9,9,9,9}][[All,1]]-1] (* Harvey P. Dale, Jan 12 2023 *)