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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 19 |
| 4 | 211 |
| 5 | 3651 |
| 6 | 90921 |
| 7 | 3081513 |
| 8 | 136407699 |
| 9 | 7642177651 |
| 10 | 528579161353 |
| 11 | 44237263696473 |
| 12 | 4405990782649369 |
| 13 | 515018848029036937 |
| 14 | 69818743428262376523 |
| 15 | 10865441556038181291819 |
| 16 | 1923889742567310611949459 |
| 17 | 384565973956329859109177427 |
| 18 | 86180438505835750284241676121 |
[1,1,3,19,211,3651,90921,3081513,136407699, 7642177651,528579161353,44237263696473, 4405990782649369,515018848029036937, 69818743428262376523,10865441556038181291819, 1923889742567310611949459, 384565973956329859109177427, 86180438505835750284241676121] |