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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 48 |
| 2 | 756 |
| 3 | 6720 |
| 4 | 41580 |
| 5 | 199584 |
| 6 | 792792 |
| 7 | 2718144 |
| 8 | 8281845 |
| 9 | 22902880 |
| 10 | 58402344 |
| 11 | 139007232 |
| 12 | 311800944 |
| 13 | 664191360 |
| 14 | 1352103840 |
| 15 | 2644114176 |
| 16 | 4988699793 |
| 17 | 9114302736 |
| 18 | 16175074300 |
| 19 | 27959131200 |
| 20 | 47181033900 |
| 21 | 77886151200 |
| 22 | 126001769400 |
| 23 | 200078424000 |
| 24 | 312275179125 |
[1,48,756,6720,41580,199584,792792,2718144, 8281845,22902880,58402344,139007232,311800944, 664191360,1352103840,2644114176,4988699793, 9114302736,16175074300,27959131200,47181033900, 77886151200,126001769400,200078424000, 312275179125] |