n | a(n) |
---|---|
0 | 2 |
1 | 1 |
2 | 0 |
3 | 2 |
4 | 6 |
5 | 16 |
6 | 60 |
7 | 272 |
8 | 1386 |
9 | 7936 |
10 | 50520 |
11 | 353792 |
12 | 2702766 |
13 | 22368256 |
14 | 199360980 |
15 | 1903757312 |
16 | 19391512146 |
17 | 209865342976 |
18 | 2404879675440 |
19 | 29088885112832 |
20 | 370371188237526 |
21 | 4951498053124096 |
22 | 69348874393137900 |
[2,1,0,2,6,16,60,272,1386,7936,50520,353792, 2702766,22368256,199360980,1903757312,19391512146, 209865342976,2404879675440,29088885112832, 370371188237526,4951498053124096, 69348874393137900] |