n | a(n) |
---|---|
0 | 0 |
1 | 1 |
2 | 6 |
3 | 40 |
4 | 264 |
5 | 1744 |
6 | 11520 |
7 | 76096 |
8 | 502656 |
9 | 3320320 |
10 | 21932544 |
11 | 144876544 |
12 | 956989440 |
13 | 6321442816 |
14 | 41756614656 |
15 | 275825459200 |
16 | 1821979213824 |
17 | 12035177119744 |
18 | 79498979573760 |
19 | 525134585921536 |
20 | 3468803433824256 |
[0,1,6,40,264,1744,11520,76096,502656,3320320, 21932544,144876544,956989440,6321442816, 41756614656,275825459200,1821979213824, 12035177119744,79498979573760,525134585921536, 3468803433824256] |