n | a(n) |
---|---|
1 | 1 |
2 | 0 |
3 | 255 |
4 | 624 |
5 | 14640 |
6 | 65280 |
7 | 707280 |
8 | 4100000 |
9 | 33361920 |
10 | 214344240 |
11 | 1568239200 |
12 | 10485693840 |
13 | 73680216480 |
14 | 500245705680 |
15 | 3461445351120 |
16 | 23639283000000 |
17 | 162614549665680 |
18 | 1113034754027520 |
19 | 7639424429247600 |
20 | 52333710967281120 |
21 | 358890347608872240 |
[1,0,255,624,14640,65280,707280,4100000,33361920, 214344240,1568239200,10485693840,73680216480, 500245705680,3461445351120,23639283000000, 162614549665680,1113034754027520,7639424429247600, 52333710967281120,358890347608872240] |