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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 10 |
| 3 | 94 |
| 4 | 880 |
| 5 | 8236 |
| 6 | 77080 |
| 7 | 721384 |
| 8 | 6751360 |
| 9 | 63185296 |
| 10 | 591344800 |
| 11 | 5534336224 |
| 12 | 51795293440 |
| 13 | 484746917056 |
| 14 | 4536697409920 |
| 15 | 42458492596864 |
| 16 | 397364741509120 |
| 17 | 3718896459510016 |
| 18 | 34804776146045440 |
| 19 | 325734382703394304 |
| 20 | 3048515170157670400 |
| 21 | 28530745405356338176 |
[0,1,10,94,880,8236,77080,721384,6751360,63185296, 591344800,5534336224,51795293440,484746917056, 4536697409920,42458492596864,397364741509120, 3718896459510016,34804776146045440, 325734382703394304,3048515170157670400, 28530745405356338176] |