A321034 - cp's OEIS frontend

A321034 Number of words of length 3n such that all letters of the quaternary alphabet occur at least once and are introduced in ascending order and which can be built by repeatedly inserting triples of identical letters into the initially empty word.

n	a(n)
4	55
5	1820
6	42228
7	859180
8	16482191
9	307525140
10	5665789450
11	103894641488
12	1904303218783
13	34970000393120
14	644169388645755
15	11909742222826580
16	221052371765382039
17	4118875328648495940
18	77037256813624307478
19	1446046251457910719288
20	27235202791173787953695

[55, 1820, 42228, 859180, 16482191, 307525140, 5665789450, 103894641488, 1904303218783, 34970000393120, 644169388645755, 11909742222826580, 221052371765382039, 4118875328648495940, 77037256813624307478, 1446046251457910719288, 27235202791173787953695]

cp's OEIS Frontend

A321034 Number of words of length 3n such that all letters of the quaternary alphabet occur at least once and are introduced in ascending order and which can be built by repeatedly inserting triples of identical letters into the initially empty word.

Table of values

List of values