A212412 Parity of curling number of binary expansion of n.

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

Offset

0

Links

Reinhard Zumkeller, Table of n, a(n) for n = 0..10000

Index entries for sequences related to binary expansion of n.

Formula

a(n) = A181935(n) mod 2.

a(A212440(n)) = 0 and a(A212441(n)) = 1.

A212439(n) = 2*n + a(n).

a(n) = A000035(A181935(n)). - Omar E. Pol, Oct 28 2013

Mathematica

f[n_, e_] := Module[{d = IntegerDigits[n, 2^e]}, Length[Split[d][[-1]]] - If[SameQ @@ d && Mod[n, 2^e] < 2^(e - 1), 1, 0]]; a[n_] := Mod[Max[Table[f[n, e], {e, Range[Max[1, Floor[Log2[n]]]]}]], 2]; a[0] = 1; Array[a, 100, 0] (* Amiram Eldar, Apr 08 2025 *)

Prog

(Haskell)
a212412 = (`mod` 2) . a181935

Crossrefs

Cf. A000035, A181935, A212439, A212440, A212441, A212444.

Sequence in context: A325898 A117904 A259030 * A185906 A071003 A071002

Adjacent sequences: A212409 A212410 A212411 * A212413 A212414 A212415

Keyword

nonn,base

Author

Reinhard Zumkeller, May 17 2012

Status

approved