n | a(n) |
---|---|
1 | 0 |
2 | 20 |
3 | 96 |
4 | 465 |
5 | 2608 |
6 | 15077 |
7 | 89811 |
8 | 544302 |
9 | 3349328 |
10 | 20823047 |
11 | 130535918 |
12 | 823585242 |
13 | 5221057054 |
14 | 33231082276 |
15 | 212180118775 |
16 | 1358528423728 |
17 | 8718262087314 |
18 | 56062919553225 |
19 | 361148981248207 |
20 | 2330144611056838 |
[0,20,96,465,2608,15077,89811,544302,3349328, 20823047,130535918,823585242,5221057054, 33231082276,212180118775,1358528423728, 8718262087314,56062919553225,361148981248207, 2330144611056838] |