n | a(n) |
---|---|
0 | 0 |
1 | 0 |
2 | 0 |
3 | 3 |
4 | 28 |
5 | 180 |
6 | 990 |
7 | 5005 |
8 | 24024 |
9 | 111384 |
10 | 503880 |
11 | 2238390 |
12 | 9806280 |
13 | 42493880 |
14 | 182530530 |
15 | 778439025 |
16 | 3300049200 |
17 | 13919756400 |
18 | 58462976880 |
19 | 244639718730 |
20 | 1020422356200 |
21 | 4244365452600 |
22 | 17610393500700 |
23 | 72907029092898 |
[0,0,0,3,28,180,990,5005,24024,111384,503880, 2238390,9806280,42493880,182530530,778439025, 3300049200,13919756400,58462976880,244639718730, 1020422356200,4244365452600,17610393500700, 72907029092898] |