The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 24 |
| 5 | 120 |
| 6 | 720 |
| 7 | 5040 |
| 8 | 37440 |
| 9 | 303912 |
| 10 | 2690304 |
| 11 | 25901984 |
| 12 | 269965600 |
| 13 | 3126293480 |
| 14 | 38002845800 |
| 15 | 508011792988 |
| 16 | 7128791775500 |
[1,2,6,24,120,720,5040,37440,303912,2690304, 25901984,269965600,3126293480,38002845800, 508011792988,7128791775500] |