A071152 - cp's OEIS frontend

A071152 Łukasiewicz words for the rooted plane binary trees (interpretation d in Stanley's exercise 19) with the last leaf implicit, i.e., these words are given without the last trailing zero, except for the null tree which is encoded as 0.

n	a(n)
0	0
1	20
2	2020
3	2200
4	202020
5	202200
6	220020
7	220200
8	222000
9	20202020
10	20202200
11	20220020
12	20220200
13	20222000
14	22002020
15	22002200
16	22020020
17	22020200
18	22022000
19	22200020
20	22200200
21	22202000
22	22220000
23	2020202020
24	2020202200

[0, 20, 2020, 2200, 202020, 202200, 220020, 220200, 222000, 20202020, 20202200, 20220020, 20220200, 20222000, 22002020, 22002200, 22020020, 22020200, 22022000, 22200020, 22200200, 22202000, 22220000, 2020202020, 2020202200]

cp's OEIS Frontend

A071152 Łukasiewicz words for the rooted plane binary trees (interpretation d in Stanley's exercise 19) with the last leaf implicit, i.e., these words are given without the last trailing zero, except for the null tree which is encoded as 0.

Table of values

List of values