n | a(n) |
---|---|
1 | 0 |
2 | 2 |
3 | 12 |
4 | 60 |
5 | 288 |
6 | 1368 |
7 | 6480 |
8 | 30672 |
9 | 145152 |
10 | 686880 |
11 | 3250368 |
12 | 15380928 |
13 | 72783360 |
14 | 344414592 |
15 | 1629787392 |
16 | 7712236800 |
17 | 36494696448 |
18 | 172694757888 |
19 | 817200368640 |
20 | 3867033664512 |
21 | 18298999775232 |
22 | 86591796664320 |
23 | 409756781334528 |
[0,2,12,60,288,1368,6480,30672,145152,686880, 3250368,15380928,72783360,344414592,1629787392, 7712236800,36494696448,172694757888,817200368640, 3867033664512,18298999775232,86591796664320, 409756781334528] |