n | a(n) |
---|---|
0 | 0 |
1 | 1 |
2 | 7 |
3 | 48 |
4 | 327 |
5 | 2221 |
6 | 15060 |
7 | 102012 |
8 | 690519 |
9 | 4671819 |
10 | 31596447 |
11 | 213633696 |
12 | 1444131108 |
13 | 9760401756 |
14 | 65957919496 |
15 | 445671648228 |
16 | 3011064814455 |
17 | 20341769686311 |
18 | 137412453018933 |
19 | 928188965638464 |
20 | 6269358748632207 |
21 | 42343731580741821 |
[0,1,7,48,327,2221,15060,102012,690519,4671819, 31596447,213633696,1444131108,9760401756, 65957919496,445671648228,3011064814455, 20341769686311,137412453018933,928188965638464, 6269358748632207,42343731580741821] |