n | a(n) |
---|---|
0 | 0 |
1 | 1 |
2 | 4 |
3 | 15 |
4 | 56 |
5 | 205 |
6 | 732 |
7 | 2555 |
8 | 8752 |
9 | 29529 |
10 | 98420 |
11 | 324775 |
12 | 1062888 |
13 | 3454373 |
14 | 11160268 |
15 | 35872275 |
16 | 114791264 |
17 | 365897137 |
18 | 1162261476 |
19 | 3680494655 |
20 | 11622614680 |
21 | 36611236221 |
22 | 115063885244 |
23 | 360882185515 |
24 | 1129718145936 |
[0,1,4,15,56,205,732,2555,8752,29529,98420,324775, 1062888,3454373,11160268,35872275,114791264, 365897137,1162261476,3680494655,11622614680, 36611236221,115063885244,360882185515, 1129718145936] |