n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 3 |
3 | 6 |
4 | 20 |
5 | 70 |
6 | 302 |
7 | 1386 |
8 | 6902 |
9 | 35862 |
10 | 194202 |
11 | 1082642 |
12 | 6191680 |
13 | 36141118 |
14 | 214715244 |
15 | 1294849186 |
16 | 7911159522 |
17 | 48888093910 |
18 | 305165808290 |
19 | 1921992409066 |
20 | 12202404037088 |
21 | 78031629139246 |
22 | 502263432618224 |
23 | 3252160882871210 |
[1,1,3,6,20,70,302,1386,6902,35862,194202,1082642, 6191680,36141118,214715244,1294849186,7911159522, 48888093910,305165808290,1921992409066, 12202404037088,78031629139246,502263432618224, 3252160882871210] |