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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 11 |
| 4 | 156 |
| 5 | 3291 |
| 6 | 88226 |
| 7 | 2875398 |
| 8 | 110100183 |
| 9 | 4841244682 |
| 10 | 240373761685 |
| 11 | 13302190764348 |
| 12 | 811959804656631 |
| 13 | 54199237928855551 |
| 14 | 3927985314859401651 |
| 15 | 307182890826521602838 |
| 16 | 25785326923948811144846 |
| 17 | 2312543296773573900444136 |
| 18 | 220690745096282461500094088 |
[1,1,1,11,156,3291,88226,2875398,110100183, 4841244682,240373761685,13302190764348, 811959804656631,54199237928855551, 3927985314859401651,307182890826521602838, 25785326923948811144846,2312543296773573900444136, 220690745096282461500094088] |