A283714 a(n) is the first occurrence after a(n-1) of the n-th digit in the decimal expansion of Pi-3, beginning with a(0)=1.

1, 3, 19, 37, 48, 55, 63, 69, 90, 91, 109, 113, 122, 139, 144, 170, 173, 194, 197, 201, 211, 221, 226, 227, 230, 231, 233, 237, 241, 242, 247, 252, 264, 275, 279, 305, 321, 324, 328, 343, 344, 347, 353, 358, 388, 391, 401, 405, 411, 417, 421, 444, 447, 456, 493, 496, 506, 511, 527, 528, 530, 534, 542

Offset

0,2

Comments

Skip the first decimal digit of Pi, and then look for the first occurrence of each of the digits in order, only moving forward.

This sequence arose as a result of the claim that the digits of Pi appear in order again later on, if you allow gaps between subsequent digits.

a(n) ~ 10n. - Robert G. Wilson v, Mar 15 2017

Links

Robert G. Wilson v, Table of n, a(n) for n = 0..10000 (corrected by Ray Chandler, Jan 19 2019)

Example

a(1) = 3, because the first occurrence of the first decimal digit of Pi after the first decimal digit is at the 3rd decimal digit.
a(2) = 19, because the next occurrence of the second decimal digit of Pi after the 3rd decimal digit is at the 19th decimal digit.

Mathematica

pid = RealDigits[Pi - 3, 10, 10000][[1]]; a[0] = 1; a[n_] := a[n] = SelectFirst[ Flatten[ Position[ pid, pid[[n]], 1, 200]], a[n -1] < # &]; Array[a, 100] (* Robert G. Wilson v, Mar 15 2017 *)

Crossrefs

Cf. A000796.

Sequence in context: A178201 A062291 A106082 * A187828 A088786 A147237

Adjacent sequences: A283711 A283712 A283713 * A283715 A283716 A283717

Keyword

nonn,base,easy

Author

Christian Perfect, Mar 15 2017

Status

approved