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Positions of -1 in A284793.
7

%I #9 Jun 25 2017 10:47:17

%S 2,6,8,10,14,18,20,24,26,30,32,34,38,42,44,46,50,54,56,60,62,64,68,72,

%T 74,78,80,82,86,90,92,96,98,102,104,106,110,114,116,118,122,126,128,

%U 132,134,138,140,142,146,150,152,154,158,162,164,168,170,172,176

%N Positions of -1 in A284793.

%C This sequence and A284795 and A284796 form a partition of the positive integers. For n>=1, we have 3n-a(n) in {0,1,2}, 3*n+2-A284795(n) in {0,1,2,3}, and 3*n-2-A284796(n) in {0,1}.

%C A284793 = (1,-1,0,1,0,-1,1,-1,1,-1,0,1,0,-1,0,1,0,-1,1,-1,0,1,0,-1, ... ); thus

%C A284794 = (2,6,8,10,14,...)

%C A284795 = (3,5,11,13,15,...)

%C A284796 = (1,4,7,9,12,15,...).

%H Clark Kimberling, <a href="/A284794/b284794.txt">Table of n, a(n) for n = 1..10000</a>

%t s = Nest[Flatten[# /. {0 -> {0, 1}, 1 -> {0, 0, 1, 1}}] &, {0}, 7] (* A284775 *)

%t d = Differences[s] (* A284793 *)

%t e = Flatten[Position[d, -1]] (* A284794 *)

%t Flatten[Position[d, 0]] (* A284795 *)

%t Flatten[Position[d, 1]] (* A284796 *)

%t e/2 (* positions of 0 in A189664 *)

%Y Cf. A284793, A284795, A284796, A189664, A284882.

%K nonn,easy

%O 1,1

%A _Clark Kimberling_, Apr 14 2017