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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 8 |
| 3 | 75 |
| 4 | 688 |
| 5 | 6329 |
| 6 | 58200 |
| 7 | 535219 |
| 8 | 4921952 |
| 9 | 45263025 |
| 10 | 416245672 |
| 11 | 3827858651 |
| 12 | 35201571600 |
| 13 | 323719017961 |
| 14 | 2976969431288 |
| 15 | 27376664647875 |
| 16 | 251759980927168 |
| 17 | 2315223158543969 |
| 18 | 21291145058550600 |
| 19 | 195796615212388459 |
| 20 | 1800575517343164272 |
| 21 | 16558366906081587225 |
| 22 | 152273265939427504792 |
[0,1,8,75,688,6329,58200,535219,4921952,45263025, 416245672,3827858651,35201571600,323719017961, 2976969431288,27376664647875,251759980927168, 2315223158543969,21291145058550600, 195796615212388459,1800575517343164272, 16558366906081587225,152273265939427504792] |