n | a(n) |
---|---|
0 | 0 |
1 | 1 |
2 | 3 |
3 | 9 |
4 | 36 |
5 | 144 |
6 | 651 |
7 | 3015 |
8 | 14634 |
9 | 72654 |
10 | 369063 |
11 | 1904985 |
12 | 9971889 |
13 | 52788393 |
14 | 282161025 |
15 | 1520597895 |
16 | 8253281871 |
17 | 45075359277 |
18 | 247534382298 |
19 | 1365994896264 |
20 | 7571065357620 |
21 | 42127865408028 |
22 | 235246997219400 |
23 | 1317894484506336 |
[0,1,3,9,36,144,651,3015,14634,72654,369063, 1904985,9971889,52788393,282161025,1520597895, 8253281871,45075359277,247534382298,1365994896264, 7571065357620,42127865408028,235246997219400, 1317894484506336] |