n | a(n) |
---|---|
1 | 4 |
2 | 6 |
3 | 4 |
4 | 15 |
5 | 72 |
6 | 266 |
7 | 1044 |
8 | 3780 |
9 | 14056 |
10 | 51132 |
11 | 188604 |
12 | 693845 |
13 | 2572920 |
14 | 9566046 |
15 | 35758628 |
16 | 134134080 |
17 | 505159200 |
18 | 1908539864 |
19 | 7233104844 |
20 | 27486455049 |
21 | 104713295712 |
22 | 399817073946 |
23 | 1529746919604 |
[4,6,4,15,72,266,1044,3780,14056,51132,188604, 693845,2572920,9566046,35758628,134134080, 505159200,1908539864,7233104844,27486455049, 104713295712,399817073946,1529746919604] |