A283768 Numbers k such that U(k) is odd, where U = A001950 = upper Wythoff sequence.

2, 3, 5, 6, 9, 12, 15, 16, 18, 19, 22, 25, 28, 29, 31, 32, 34, 35, 38, 41, 42, 44, 45, 47, 48, 51, 54, 55, 57, 58, 60, 61, 64, 67, 70, 71, 73, 74, 77, 80, 83, 84, 86, 87, 89, 90, 93, 96, 97, 99, 100, 102, 103, 106, 109, 110, 112, 113, 115, 116, 119, 122, 125

Offset: 1

Author

Clark Kimberling, Mar 17 2017

Keywords

• nonn
• easy

Comments

Complement of A283767.

Links

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

Crossrefs

Cf. A001950, A001622, A283765, A283767.

Programs

Mathematica

r = GoldenRatio^2; z = 250; t = Table[Floor[n*r], {n, 1, z}]; u = Mod[t, 2];
Flatten[Position[u, 0]]  (* A283767 *)
Flatten[Position[u, 1]]  (* A283768 *)

Formula

a(n+1) - a(n) is in {1,2,3} for every n.