A189081 - OEIS

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A189081

Zero-one sequence based on the sequence floor(n*sqrt(2)): a(A001951(k))=a(k); a(A001952(k))=1-a(k); a(1)=0, a(2)=1.

0, 1, 1, 1, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 0, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 0, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 0, 1, 0, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0

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OFFSET

LINKS

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

EXAMPLE

Let u=A001951=(Beatty sequence for sqrt(2)) and v=A001952=(Beatty sequence for 2+sqrt(2)). Then A189081 is the sequence a given by a(u(k))=a(k); a(v(k))=1-a(k), where a(0)=0 and a(1)=1.

MATHEMATICA

r = 2^(1/2); u[n_] := Floor[r*n]; (*A001951*)

v[n_] := Floor[(2 + r) n]; (*A001952*)

a[1] = 0; a[2] = 1; h = 200;

c = Table[u[n], {n, 1, h}];

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

Table[a[d[[n]]] = 1 - a[n], {n, 1, h - 1}]; (*A189081*)

Table[a[c[[n]]] = a[n], {n, 1, h}] (*A189081*)

Flatten[Position[%, 0]] (*A189082*)

Flatten[Position[%%, 1]] (*A189083*)

CROSSREFS

Cf. A189078, A189082, A189083, A188967.