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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 30 |
| 2 | 5310 |
| 3 | 2453220 |
| 4 | 910100190 |
| 5 | 409796742600 |
| 6 | 181276113779460 |
| 7 | 84362079365838960 |
| 8 | 39636500385830239350 |
| 9 | 18986938020443181757410 |
| 10 | 9186944625290601368703000 |
| 11 | 4491611148118819794144792660 |
| 12 | 2212757749022582852433835771860 |
| 13 | 1097546094982154634980848454416920 |
[1,30,5310,2453220,910100190,409796742600, 181276113779460,84362079365838960, 39636500385830239350,18986938020443181757410, 9186944625290601368703000, 4491611148118819794144792660, 2212757749022582852433835771860, 1097546094982154634980848454416920] |