A283766 Numbers k such that L(k) is odd, where L = A000201 = lower Wythoff sequence.

1, 2, 6, 7, 11, 12, 13, 16, 17, 18, 21, 22, 23, 27, 28, 32, 33, 34, 37, 38, 39, 42, 43, 44, 48, 49, 53, 54, 58, 59, 60, 63, 64, 65, 69, 70, 74, 75, 79, 80, 81, 84, 85, 86, 90, 91, 95, 96, 100, 101, 102, 105, 106, 107, 110, 111, 112, 116, 117, 121, 122, 123

Offset: 1

Author

Clark Kimberling, Mar 17 2017

Keywords

• nonn
• easy

Comments

Complement of A283765.

Links

• Clark Kimberling, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A000201, A001622, A105774, A283765, A283768.

Cf. A085002 (characteristic function), A085003 (a left inverse).

Programs

Mathematica

r = GoldenRatio; z = 250; t = Table[Floor[n*r], {n, 1, z}]; u = Mod[t, 2];
Flatten[Position[u, 0]]  (* A283765 *)
Flatten[Position[u, 1]]  (* A283766 *)

Formula

a(n+1) - a(n) is in {1,3,4} for every n.

A085003(a(n)) = n for all n >= 1. - Antti Karttunen, Mar 17 2017