n | a(n) |
---|---|
0 | 1 |
1 | 2 |
2 | 16 |
3 | 100 |
4 | 660 |
5 | 4482 |
6 | 30886 |
7 | 215364 |
8 | 1515000 |
9 | 10730800 |
10 | 76426846 |
11 | 546792056 |
12 | 3926775646 |
13 | 28290272420 |
14 | 204375145480 |
15 | 1479963148220 |
16 | 10739326203132 |
17 | 78072933869364 |
18 | 568503202324540 |
19 | 4145718464390120 |
20 | 30271771382355430 |
21 | 221305746414518180 |
[1,2,16,100,660,4482,30886,215364,1515000, 10730800,76426846,546792056,3926775646, 28290272420,204375145480,1479963148220, 10739326203132,78072933869364,568503202324540, 4145718464390120,30271771382355430, 221305746414518180] |