cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A355164 a(n) = exp(-1/3) * Sum_{k>=0} (3*k + 2)^n / (3^k * k!).

Table of values

n a(n)
0 1
1 3
2 12
3 63
4 405
5 3024
6 25515
7 239355
8 2465478
9 27600669
10 333051669
11 4303119330
12 59202612693
13 863285928327
14 13288589222508
15 215177742933579
16 3654114236490393
17 64902307993517160
18 1202782377224829015
19 23207417212751493327
20 465302639045308247262
21 9677171073270491712513
22 208434297638273958963225

List of values

[1, 3, 12, 63, 405, 3024, 25515, 239355, 2465478, 27600669, 333051669, 4303119330, 59202612693, 863285928327, 13288589222508, 215177742933579, 3654114236490393, 64902307993517160, 1202782377224829015, 23207417212751493327, 465302639045308247262, 9677171073270491712513, 208434297638273958963225]