n | a(n) |
---|---|
1 | 2 |
2 | 2 |
3 | 4 |
4 | 12 |
5 | 30 |
6 | 60 |
7 | 154 |
8 | 404 |
9 | 1046 |
10 | 2540 |
11 | 6720 |
12 | 17484 |
13 | 46522 |
14 | 120300 |
15 | 323800 |
16 | 856032 |
17 | 2315578 |
18 | 6151080 |
19 | 16745530 |
20 | 44921984 |
21 | 122790698 |
22 | 331148108 |
23 | 908909558 |
24 | 2465359580 |
25 | 6788313198 |
26 | 18491757632 |
27 | 51067082988 |
[2,2,4,12,30,60,154,404,1046,2540,6720,17484, 46522,120300,323800,856032,2315578,6151080, 16745530,44921984,122790698,331148108,908909558, 2465359580,6788313198,18491757632,51067082988] |