n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 4 |
3 | 16 |
4 | 98 |
5 | 650 |
6 | 5492 |
7 | 50468 |
8 | 543252 |
9 | 6375668 |
10 | 83752144 |
11 | 1191943168 |
12 | 18563252968 |
13 | 310499073352 |
14 | 5598292885200 |
15 | 107674197010960 |
16 | 2208771882047120 |
17 | 48025183073776016 |
18 | 1105381958987588672 |
19 | 26817991185065949440 |
20 | 684717365565811694880 |
21 | 18341702444087583851936 |
[1,1,4,16,98,650,5492,50468,543252,6375668, 83752144,1191943168,18563252968,310499073352, 5598292885200,107674197010960,2208771882047120, 48025183073776016,1105381958987588672, 26817991185065949440,684717365565811694880, 18341702444087583851936] |