n | a(n) |
---|---|
1 | 1 |
2 | 4 |
3 | 9 |
4 | 28 |
5 | 85 |
6 | 426 |
7 | 3409 |
8 | 23864 |
9 | 167049 |
10 | 1837540 |
11 | 18375401 |
12 | 128627808 |
13 | 1157650273 |
14 | 10418852458 |
15 | 83350819665 |
16 | 1250262294976 |
17 | 22504721309569 |
18 | 382580262262674 |
19 | 4973543409414763 |
20 | 64656064322391920 |
[1,4,9,28,85,426,3409,23864,167049,1837540, 18375401,128627808,1157650273,10418852458, 83350819665,1250262294976,22504721309569, 382580262262674,4973543409414763, 64656064322391920] |