A135133 a(n) = floor(S2(n)/3) mod 2, where S2(n) denotes the binary weight of n.

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

Offset: 0

Author

Ctibor O. Zizka, Feb 12 2008

Keywords

• nonn
• base
• easy

Comments

A generalized Thue-Morse sequence.

Links

• Nathaniel Johnston, Table of n, a(n) for n = 0..10000
• Ricardo Astudillo, On a class of Thue-Morse type sequences, Journal of Integer Sequences, Vol. 6 (2003), Article 03.4.2.

Crossrefs

Cf. A000120, A010060.

Programs

Maple

S2 := proc(n) return add(d, d=convert(n,base,2)): end: A135133 := proc(n) return floor(S2(n)/3) mod 2: end: seq(A135133(n),n=0..104); # Nathaniel Johnston, May 06 2011

Mathematica

Table[Mod[Floor[(Plus @@ IntegerDigits[n, 2])/3], 2], {n, 0, 50}] (* G. C. Greubel, Sep 28 2016 *)