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A293829 Numbers k such that (d(k), d(k+1)) = (0,1) in the base-2 digits d(i) of Pi. 4
4, 7, 12, 19, 22, 24, 26, 30, 34, 39, 41, 44, 48, 54, 58, 61, 64, 69, 72, 77, 81, 86, 88, 92, 94, 104, 107, 115, 120, 123, 127, 130, 132, 135, 142, 145, 148, 156, 160, 164, 166, 169, 173, 180, 185, 189, 198, 204, 206, 210, 216, 218, 221, 226, 230, 235, 238 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Clark Kimberling, Table of n, a(n) for n = 1..10000

EXAMPLE

This sequence together with A293828, A293830, and A293831 partition the positive integers.

(d(i)) = (1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0,...) = A004601, in which (0,1) first occurs as (a(4),a(5)).

MATHEMATICA

z = 100; s = StringJoin[Map[ToString, First[RealDigits[N[Pi], 10000], 2]]]];

Take[Map[#[[1]]&, StringPosition[s, "00"]], z] (*A293828*)

Take[Map[#[[1]]&, StringPosition[s, "01"]], z] (*A293829*)

Take[Map[#[[1]]&, StringPosition[s, "10"]], z] (*A293830*)

Take[Map[#[[1]]&, StringPosition[s, "11"]], z] (*A293831*)

(* Peter J. C. Moses, Oct 15 2017 *)

CROSSREFS

Cf. A004601, A293828, A293830, A293831.

Sequence in context: A132297 A007333 A097536 * A022809 A297554 A188554

Adjacent sequences:  A293826 A293827 A293828 * A293830 A293831 A293832

KEYWORD

nonn,easy,base

AUTHOR

Clark Kimberling, Oct 20 2017

STATUS

approved

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Last modified April 9 20:46 EDT 2020. Contains 333363 sequences. (Running on oeis4.)