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A293789
Numbers k such that (d(k), d(k+1)) = (1,0) in the base-2 digits d(i) of sqrt(3).
4
2, 6, 9, 12, 18, 20, 24, 26, 31, 34, 39, 43, 46, 48, 50, 52, 57, 62, 65, 68, 71, 73, 77, 79, 84, 87, 89, 93, 102, 106, 110, 118, 122, 126, 129, 132, 135, 139, 142, 149, 151, 155, 159, 163, 165, 171, 174, 176, 179, 186, 190, 195, 201, 204, 210, 212, 216, 219
OFFSET
1,1
COMMENTS
This sequence together with A293787, A293788, and A293790 partition the positive integers.
LINKS
EXAMPLE
(d(i)) = (1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 0, 0, 1, 1, 1, 1, 0,...) = A004547, in which (1,0) first occurs as (a(2),a(3)).
MATHEMATICA
z = 100; s = StringJoin[Map[ToString, First[RealDigits[N[Sqrt[3], 10000], 2]]]];
Take[Map[#[[1]]&, StringPosition[s, "00"]], z] (*A293787*)
Take[Map[#[[1]]&, StringPosition[s, "01"]], z] (*A293788*)
Take[Map[#[[1]]&, StringPosition[s, "10"]], z] (*A293789*)
Take[Map[#[[1]]&, StringPosition[s, "11"]], z] (*A293790*)
(* Peter J. C. Moses, Oct 15 2017 *)
CROSSREFS
KEYWORD
nonn,easy,base
AUTHOR
Clark Kimberling, Oct 19 2017
STATUS
approved