n | a(n) |
---|---|
1 | 0 |
2 | 3 |
3 | 8 |
4 | 55 |
5 | 294 |
6 | 1883 |
7 | 11920 |
8 | 78255 |
9 | 517050 |
10 | 3451712 |
11 | 23156964 |
12 | 156076271 |
13 | 1055435486 |
14 | 7157673375 |
15 | 48656943008 |
16 | 331450961443 |
17 | 2261939399694 |
18 | 15461147598417 |
19 | 105834401893220 |
20 | 725394224374344 |
21 | 4977715076045096 |
[0,3,8,55,294,1883,11920,78255,517050,3451712, 23156964,156076271,1055435486,7157673375, 48656943008,331450961443,2261939399694, 15461147598417,105834401893220,725394224374344, 4977715076045096] |