A240609 - cp's OEIS frontend

A240609 Number of n-length words w over a 3-ary alphabet such that w is empty or a prefix z concatenated with letter a_i and i=1 or 0 < #(z,a_{i-1}) >= #(z,a_i), where #(z,a_i) counts the occurrences of the i-th letter in z.

n	a(n)
0	1
1	1
2	2
3	5
4	13
5	35
6	94
7	254
8	688
9	1872
10	5115
11	14038
12	38689
13	107055
14	297336
15	828699
16	2317098
17	6498114
18	18273861
19	51521238
20	145604868
21	412407942
22	1170507375
23	3328570513
24	9482518041
25	27059673745
26	77340925350
27	221382318131
28	634578781229
29	1821388557507

[1, 1, 2, 5, 13, 35, 94, 254, 688, 1872, 5115, 14038, 38689, 107055, 297336, 828699, 2317098, 6498114, 18273861, 51521238, 145604868, 412407942, 1170507375, 3328570513, 9482518041, 27059673745, 77340925350, 221382318131, 634578781229, 1821388557507]

cp's OEIS Frontend

A240609 Number of n-length words w over a 3-ary alphabet such that w is empty or a prefix z concatenated with letter a_i and i=1 or 0 < #(z,a_{i-1}) >= #(z,a_i), where #(z,a_i) counts the occurrences of the i-th letter in z.

Table of values

List of values