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A189212
Zero-one sequence based on the hexagonal numbers: a(A000384(k))=a(k); a(v(k))=1-a(k), where v=A183218 and a(1)=0.
4
0, 1, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 1
OFFSET
1
MATHEMATICA
u[n_] := n(2n-1); (*A000384*)
a[1] = 0; h = 128;
c = (u[#1] &) /@ Range[2h];
d = (Complement[Range[Max[#1]], #1] &)[c]; (*A183218*)
Table[a[d[[n]]] = 1 - a[n], {n, 1, h - 1}]; (*A189212*)
Table[a[c[[n]]] = a[n], {n, 1, h}] (*A189212*)
Flatten[Position[%, 0]] (*A189213*)
Flatten[Position[%%, 1]] (*A189214*)
CROSSREFS
KEYWORD
nonn
AUTHOR
Clark Kimberling, Apr 18 2011
STATUS
approved