n | a(n) |
---|---|
1 | 4 |
2 | 15 |
3 | 80 |
4 | 446 |
5 | 2477 |
6 | 13752 |
7 | 76375 |
8 | 424115 |
9 | 2355221 |
10 | 13079032 |
11 | 72630752 |
12 | 403334385 |
13 | 2239803950 |
14 | 12438120321 |
15 | 69071597937 |
16 | 383569664377 |
17 | 2130046094920 |
18 | 11828611039210 |
19 | 65686859759121 |
20 | 364773474308192 |
21 | 2025666747456127 |
[4,15,80,446,2477,13752,76375,424115,2355221, 13079032,72630752,403334385,2239803950, 12438120321,69071597937,383569664377, 2130046094920,11828611039210,65686859759121, 364773474308192,2025666747456127] |