n | a(n) |
---|---|
1 | 0 |
2 | 0 |
3 | 0 |
4 | 0 |
5 | 0 |
6 | 90 |
7 | 630 |
8 | 3780 |
9 | 18900 |
10 | 94500 |
11 | 457380 |
12 | 3825360 |
13 | 31505760 |
14 | 312432120 |
15 | 2704501800 |
16 | 22984481520 |
17 | 179863997040 |
18 | 1531709328240 |
19 | 13078616488560 |
20 | 147223414987200 |
21 | 1657733805020160 |
22 | 20131890668255520 |
23 | 226464779237447520 |
24 | 2542924546378413120 |
25 | 27053572399079688000 |
[0,0,0,0,0,90,630,3780,18900,94500,457380,3825360, 31505760,312432120,2704501800,22984481520, 179863997040,1531709328240,13078616488560, 147223414987200,1657733805020160, 20131890668255520,226464779237447520, 2542924546378413120,27053572399079688000] |