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A293828 Numbers k such that (d(k), d(k+1)) = (0,0) in the base-2 digits d(i) of Pi. 4
3, 6, 9, 10, 11, 28, 29, 32, 33, 36, 37, 38, 46, 47, 51, 52, 53, 56, 57, 63, 67, 68, 71, 75, 76, 80, 84, 85, 90, 91, 98, 99, 100, 101, 102, 103, 111, 112, 113, 114, 119, 125, 126, 129, 134, 137, 138, 139, 140, 141, 144, 147, 152, 153, 154, 155, 158, 159, 162 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

This sequence, together with A293829, A293830, and A293831, partitions the positive integers.

LINKS

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

EXAMPLE

(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 (0,0) first occurs as (a(3),a(4)).

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 *)

SequencePosition[RealDigits[Pi, 2, 200][[1]], {0, 0}][[All, 1]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Nov 09 2017 *)

CROSSREFS

Cf. A004601, A293829, A293830, A293831.

Sequence in context: A074499 A309584 A081605 * A110263 A022304 A176423

Adjacent sequences:  A293825 A293826 A293827 * A293829 A293830 A293831

KEYWORD

nonn,easy,base

AUTHOR

Clark Kimberling, Oct 20 2017

STATUS

approved

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Last modified October 15 17:24 EDT 2019. Contains 328037 sequences. (Running on oeis4.)