A135156 - cp's OEIS frontend

A135156 a(n) = number of strings of length n that can be obtained by starting with abc and repeatedly doubling any substring of length >= 2 in place.

n	a(n)
0	1
1	0
2	2
3	0
4	3
5	1
6	4
7	0
8	5
9	2
10	6
11	1
12	7
13	3
14	8
15	9
16	9
17	7
18	10
19	34
20	11
21	36
22	12
23	136
24	13
25	190
26	14
27	567
28	15
29	1018
30	16
31	2445
32	17
33	5474
34	18
35	11371
36	19
37	28233
38	20
39	57961
40	21
41	143391
42	22
43	308793
44	23
45	740519
46	24
47	1668316

[1, 0, 2, 0, 3, 1, 4, 0, 5, 2, 6, 1, 7, 3, 8, 9, 9, 7, 10, 34, 11, 36, 12, 136, 13, 190, 14, 567, 15, 1018, 16, 2445, 17, 5474, 18, 11371, 19, 28233, 20, 57961, 21, 143391, 22, 308793, 23, 740519, 24, 1668316]

cp's OEIS Frontend

A135156 a(n) = number of strings of length n that can be obtained by starting with abc and repeatedly doubling any substring of length >= 2 in place.

Table of values

List of values