n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 1 |
3 | 2 |
4 | 5 |
5 | 24 |
6 | 109 |
7 | 720 |
8 | 4521 |
9 | 40320 |
10 | 330681 |
11 | 3628800 |
12 | 36468717 |
13 | 479001600 |
14 | 5721101541 |
15 | 87178291200 |
16 | 1205289090513 |
17 | 20922789888000 |
18 | 328897528901361 |
19 | 6402373705728000 |
20 | 112769846051251797 |
21 | 2432902008176640000 |
[1,1,1,2,5,24,109,720,4521,40320,330681,3628800, 36468717,479001600,5721101541,87178291200, 1205289090513,20922789888000,328897528901361, 6402373705728000,112769846051251797, 2432902008176640000] |