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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 2 |
| 6 | 12 |
| 7 | 12 |
| 8 | 96 |
| 9 | 288 |
| 10 | 5760 |
| 11 | 5760 |
| 12 | 829440 |
| 13 | 829440 |
| 14 | 46448640 |
| 15 | 2090188800 |
| 16 | 267544166400 |
| 17 | 267544166400 |
| 18 | 346737239654400 |
| 19 | 346737239654400 |
| 20 | 1109559166894080000 |
| 21 | 209706682542981120000 |
| 22 | 73816752255129354240000 |
| 23 | 73816752255129354240000 |
[1,1,1,1,2,2,12,12,96,288,5760,5760,829440,829440, 46448640,2090188800,267544166400,267544166400, 346737239654400,346737239654400, 1109559166894080000,209706682542981120000, 73816752255129354240000,73816752255129354240000] |