A384601 Numbers k such that T(k, 1) mod 3 = 1 and T(k, 2) mod 3 = 1, where T is the Wythoff array (A035513).

2, 8, 17, 26, 32, 41, 56, 65, 71, 80, 89, 95, 104, 110, 119, 128, 134, 143, 158, 167, 173, 182, 191, 197, 206, 221, 230, 236, 245, 260, 269, 275, 284, 293, 299, 308, 323, 332, 338, 347, 356, 362, 371, 377, 386, 395, 401, 410, 425, 434, 440, 449, 458, 464

Offset

1,1

Comments

This is one of 9 sets that partition the positive integers; see the Jun 04 2025 comment in A035513.

Links

Table of n, a(n) for n=1..54.

Example

(Row 8 of T) = (19,31,50,81,...).
((Row 8 of T) mod 3) = (1,1,2,0,...), so 8 is in the list.

Mathematica

w[n_] := {Floor[n*GoldenRatio] + n - 1, 2*Floor[n*GoldenRatio] + n - 1}
t = Table[Mod[w[n], 3], {n, 1, 500}];
Flatten[Position[t, {1, 1}]]   (* A384601 *)
Flatten[Position[t, {1, 2}]]   (* A384602 *)

Crossrefs

Cf. A035513, A384602.

Sequence in context: A284395 A217192 A224865 * A192159 A066564 A357576

Adjacent sequences: A384598 A384599 A384600 * A384602 A384603 A384604

Keyword

nonn

Author

Clark Kimberling, Jun 05 2025

Status

approved