n | a(n) |
---|---|
1 | 1 |
2 | 1 |
3 | 4 |
4 | 16 |
5 | 60 |
6 | 226 |
7 | 848 |
8 | 3200 |
9 | 12120 |
10 | 46126 |
11 | 176232 |
12 | 675808 |
13 | 2599688 |
14 | 10028292 |
15 | 38777664 |
16 | 150266880 |
17 | 583395120 |
18 | 2268771670 |
19 | 8836291640 |
20 | 34461586016 |
21 | 134564376232 |
22 | 526024564572 |
23 | 2058357329184 |
[1,1,4,16,60,226,848,3200,12120,46126,176232, 675808,2599688,10028292,38777664,150266880, 583395120,2268771670,8836291640,34461586016, 134564376232,526024564572,2058357329184] |