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A189011 Zero-one sequence based on triangular numbers:  a(A000217(k))=a(k); a(A014132(k))=1-a(k); a(1)=0. 4
0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 0, 0, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1

LINKS

Table of n, a(n) for n=1..135.

EXAMPLE

Let u=A000217 and v=A014132, so that u(n)=n(n+1)/2 and v=complement(u) for n>=1.  Then a is a self-generating zero-one sequence with initial value a(1)=0 and a(u(k))=a(k); a(v(k))=1-a(k).

MATHEMATICA

u[n_] := n(n+1)/2;  (*A000217*)

a[1] = 0; h = 128;

c = (u[#1] &) /@ Range[h];

d = (Complement[Range[Max[#1]], #1] &)[c]; (*A014132*)

Table[a[d[[n]]] = 1 - a[n], {n, 1, h - 1}];

Table[a[c[[n]]] = a[n], {n, 1, h}]   (*A189011*)

Flatten[Position[%, 0]]  (*A189012*)

Flatten[Position[%%, 1]] (*A189013*)

CROSSREFS

Cf. A188967, A189012, A189013, A188973.

Sequence in context: A234046 A285565 A188076 * A189135 A219189 A029691

Adjacent sequences:  A189008 A189009 A189010 * A189012 A189013 A189014

KEYWORD

nonn

AUTHOR

Clark Kimberling, Apr 15 2011

STATUS

approved

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Last modified October 20 04:37 EDT 2019. Contains 328247 sequences. (Running on oeis4.)