n | a(n) |
---|---|
0 | 1 |
1 | 3 |
2 | 8 |
3 | 40 |
4 | 216 |
5 | 1386 |
6 | 9552 |
7 | 71820 |
8 | 571440 |
9 | 4815778 |
10 | 42465144 |
11 | 391058720 |
12 | 3738272328 |
13 | 37015339410 |
14 | 378307524768 |
15 | 3983307781956 |
16 | 43109512918560 |
17 | 478808036794306 |
18 | 5448659044584680 |
19 | 63446989372749528 |
20 | 755057167559816440 |
[1,3,8,40,216,1386,9552,71820,571440,4815778, 42465144,391058720,3738272328,37015339410, 378307524768,3983307781956,43109512918560, 478808036794306,5448659044584680, 63446989372749528,755057167559816440] |