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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 8 |
| 5 | 8 |
| 6 | 144 |
| 7 | 144 |
| 8 | 576 |
| 9 | 5184 |
| 10 | 518400 |
| 11 | 518400 |
| 12 | 2073600 |
| 13 | 2073600 |
| 14 | 101606400 |
| 15 | 914457600 |
| 16 | 14631321600 |
| 17 | 14631321600 |
| 18 | 526727577600 |
| 19 | 526727577600 |
| 20 | 52672757760000 |
| 21 | 221225582592000 |
| 22 | 6373403688960000 |
| 23 | 6373403688960000 |
| 24 | 917770131210240000 |
| 25 | 22944253280256000000 |
| 26 | 3877578804363264000000 |
[1,1,1,1,8,8,144,144,576,5184,518400,518400, 2073600,2073600,101606400,914457600,14631321600, 14631321600,526727577600,526727577600, 52672757760000,221225582592000,6373403688960000, 6373403688960000,917770131210240000, 22944253280256000000,3877578804363264000000] |