A071906 Sum of digits of 2^n (mod 2).

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

Offset

0,1

Links

G. C. Greubel, Table of n, a(n) for n = 0..10000

Mathematica

f[n_] := Mod[Plus @@ IntegerDigits[2^n], 2]; Table[ f@n, {n, 0, 104}] (* Robert G. Wilson v, May 04 2009 *)

Prog

(PARI) a(n) = sumdigits(2^n) % 2; \\ Michel Marcus, Apr 20 2017

Crossrefs

Cf. A001370.

Sequence in context: A188189 A029692 A309849 * A104107 A120532 A373156

Adjacent sequences: A071903 A071904 A071905 * A071907 A071908 A071909

Keyword

base,nonn

Author

Santi Spadaro, Jun 13 2002

Status

approved