n | a(n) |
---|---|
0 | 1 |
1 | 2 |
2 | 6 |
3 | 18 |
4 | 56 |
5 | 180 |
6 | 594 |
7 | 2002 |
8 | 6864 |
9 | 23868 |
10 | 83980 |
11 | 298452 |
12 | 1069776 |
13 | 3863080 |
14 | 14040810 |
15 | 51325650 |
16 | 188574240 |
17 | 695987820 |
18 | 2579248980 |
19 | 9593714460 |
20 | 35804293200 |
21 | 134032593240 |
22 | 503154100020 |
23 | 1893689067348 |
24 | 7144084508256 |
[1,2,6,18,56,180,594,2002,6864,23868,83980,298452, 1069776,3863080,14040810,51325650,188574240, 695987820,2579248980,9593714460,35804293200, 134032593240,503154100020,1893689067348, 7144084508256] |