A053749 Positions of 5's in the decimal expansion of Pi.

5, 9, 11, 32, 49, 52, 62, 91, 110, 131, 132, 134, 142, 144, 159, 173, 178, 179, 180, 192, 211, 214, 226, 241, 253, 257, 273, 305, 316, 317, 326, 339, 346, 356, 368, 371, 380, 390, 395, 405, 412, 414, 416, 420

Offset: 1

Author

Simon Plouffe, Feb 20 2000

Keywords

• nonn
• base

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..1000
• Index entries for sequences related to the number Pi

Crossrefs

Cf. A037004.

Programs

Mathematica

Flatten[Position[RealDigits[Pi, 10, 1000][[1]], 5]] (* Vincenzo Librandi, Oct 07 2013 *)

Formula

a(n) = A037004(n) + 1. - Georg Fischer, May 31 2021