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A248056 Positions of 0,0 in the Thue-Morse sequence (A010060). 4

%I #8 Mar 02 2020 19:28:13

%S 6,10,18,24,30,34,40,46,54,58,66,72,78,86,90,96,102,106,114,120,126,

%T 130,136,142,150,154,160,166,170,178,184,190,198,202,210,216,222,226,

%U 232,238,246,250,258,264,270,278,282,288,294,298,306,312,318,326,330

%N Positions of 0,0 in the Thue-Morse sequence (A010060).

%C Every positive integer lies in exactly one of these four sequences: A248056, A091855, A091855, A248057.

%H Clark Kimberling, <a href="/A248056/b248056.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) = 2*A091785(n) for n >= 1.

%e Thue-Morse sequence: 0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,..., so that a(1) = 6 and a(2) = 10.

%t z = 400; u = Nest[Flatten[# /. {0 -> {0, 1}, 1 -> {1, 0}}] &, {0}, 9] (* A010060 *)

%t v = Rest[u]

%t t1 = Table[If[u[[n]] == 0 && v[[n]] == 0, 1, 0], {n, 1, z}];

%t t2 = Table[If[u[[n]] == 0 && v[[n]] == 1, 1, 0], {n, 1, z}];

%t t3 = Table[If[u[[n]] == 1 && v[[n]] == 0, 1, 0], {n, 1, z}];

%t t4 = Table[If[u[[n]] == 1 && v[[n]] == 1, 1, 0], {n, 1, z}];

%t Flatten[Position[t1, 1]] (* A248056 *)

%t Flatten[Position[t2, 1]] (* A091855 *)

%t Flatten[Position[t3, 1]] (* A091785 *)

%t Flatten[Position[t4, 1]] (* A248057 *)

%t SequencePosition[ThueMorse[Range[400]],{0,0}][[All,2]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Mar 02 2020 *)

%Y Cf. A010060, A091855, A091785, A248057.

%K nonn,easy

%O 1,1

%A _Clark Kimberling_, Sep 30 2014

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Last modified April 25 11:06 EDT 2024. Contains 371967 sequences. (Running on oeis4.)