n | a(n) |
---|---|
0 | 1 |
1 | 21 |
2 | 420 |
3 | 8400 |
4 | 167790 |
5 | 3351600 |
6 | 66948210 |
7 | 1337288400 |
8 | 26712295890 |
9 | 533577313500 |
10 | 10658190898110 |
11 | 212897044846500 |
12 | 4252612111884990 |
13 | 84945799915397400 |
14 | 1696789816099808010 |
15 | 33893325895893882600 |
16 | 677018172425014524090 |
17 | 13523417772619230573300 |
[1,21,420,8400,167790,3351600,66948210,1337288400, 26712295890,533577313500,10658190898110, 212897044846500,4252612111884990, 84945799915397400,1696789816099808010, 33893325895893882600,677018172425014524090, 13523417772619230573300] |