A189728 Positions of 0 in A189727; complement of A189729.

1, 6, 9, 12, 15, 16, 21, 24, 25, 30, 33, 34, 39, 42, 43, 46, 51, 54, 57, 60, 61, 66, 69, 70, 73, 78, 81, 84, 87, 88, 93, 96, 97, 100, 105, 108, 111, 114, 115, 120, 123, 124, 127, 132, 135, 136, 141, 144, 147, 150, 151, 156, 159, 160, 165, 168, 169, 174, 177, 178, 181, 186, 189, 192, 195, 196, 201, 204, 205, 208, 213, 216, 217, 222, 225

Offset: 1

Author

Clark Kimberling, Apr 26 2011

Keywords

• nonn

Comments

See A189727.

This sequence also gives the positions of 0 in the fixed point of the morphism 0->012, 1->210, 2->120. Moreover, a(n) - a(n-1) is in {1,3,5} for n >= 1; also, 3n - a(n) is in {0, 2} for n >= 1. The first 20 numbers 3n - a(n) are 2, 0, 0, 0, 0, 2, 0, 0, 2, 0, 0, 2, 0, 0, 2, 2, 0, 0, 0, 0, with 2 in positions given by A189728. - Clark Kimberling, May 25 2017

Links

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

Crossrefs

Cf. A189727, A189729, A189730, A287401.

Programs

Mathematica

(See A189727 and A287401.)