A218479 - cp's OEIS frontend

A218479 Number of 3n-length 9-ary words, either empty or beginning with the first letter of the alphabet, that can be built by repeatedly inserting triples of identical letters into the initially empty word.

n	a(n)
0	1
1	1
2	25
3	817
4	30345
5	1215521
6	51186169
7	2233558545
8	100094682729
9	4579454148865
10	213011954187225
11	10043235050384625
12	478897402022246985
13	23054568307757054433
14	1118987674598361862585
15	54698321862693296502737
16	2690410083349269351772713

[1, 1, 25, 817, 30345, 1215521, 51186169, 2233558545, 100094682729, 4579454148865, 213011954187225, 10043235050384625, 478897402022246985, 23054568307757054433, 1118987674598361862585, 54698321862693296502737, 2690410083349269351772713]

cp's OEIS Frontend

A218479 Number of 3n-length 9-ary words, either empty or beginning with the first letter of the alphabet, that can be built by repeatedly inserting triples of identical letters into the initially empty word.

Table of values

List of values