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Positions of 1,0,1 in the Thue-Morse sequence (A010060).
2

%I #5 Oct 02 2014 22:36:07

%S 3,12,15,20,27,36,43,48,51,60,63,68,75,80,83,92,99,108,111,116,123,

%T 132,139,144,147,156,163,172,175,180,187,192,195,204,207,212,219,228,

%U 235,240,243,252,255,260,267,272,275,284,291,300,303,308,315,320,323

%N Positions of 1,0,1 in the Thue-Morse sequence (A010060).

%C Every positive integer lies in exactly one of these six sequences:

%C A248056 (positions of 0,0,1)

%C A248104 (positions of 0,1,0)

%C A157970 (positions of 1,0,0)

%C A157971 (positions of 0,1,1)

%C A248105 (positions of 1,0,1)

%C A248057 (positions of 1,1,0)

%H Clark Kimberling, <a href="/A248105/b248105.txt">Table of n, a(n) for n = 1..1000</a>

%e Thue-Morse sequence: 0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,..., so that a(1) = 3 and a(2) = 12.

%t z = 600; u = Nest[Flatten[# /. {0 -> {0, 1}, 1 -> {1, 0}}] &, {0}, 13]; v = Rest[u]; w = Rest[v]; t1 = Table[If[u[[n]] == 0 && v[[n]] == 0 && w[[n]] == 1, 1, 0], {n, 1, z}];

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

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

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

%t t5 = Table[If[u[[n]] == 1 && v[[n]] == 0 && w[[n]] == 1, 1, 0], {n, 1, z}];

%t t6 = Table[If[u[[n]] == 1 && v[[n]] == 1 && w[[n]] == 0, 1, 0], {n, 1, z}];

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

%t Flatten[Position[t2, 1]] (* A248104 *)

%t Flatten[Position[t3, 1]] (* A157970 *)

%t Flatten[Position[t4, 1]] (* A157971 *)

%t Flatten[Position[t5, 1]] (* A248105 *)

%t Flatten[Position[t6, 1]] (* A248057 *)

%Y Cf. A010060, A248056, A157970, A157971, A248104, A248057.

%K nonn,easy

%O 1,1

%A _Clark Kimberling_, Oct 01 2014