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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 18 |
| 2 | 217 |
| 3 | 2238 |
| 4 | 21493 |
| 5 | 199506 |
| 6 | 1821889 |
| 7 | 16508646 |
| 8 | 149043565 |
| 9 | 1343313114 |
| 10 | 12097677241 |
| 11 | 108911059374 |
| 12 | 980328977317 |
| 13 | 8823483334242 |
| 14 | 79413454477873 |
| 15 | 714729551160822 |
| 16 | 6432599932896349 |
| 17 | 57893535673021290 |
[1,18,217,2238,21493,199506,1821889,16508646, 149043565,1343313114,12097677241,108911059374, 980328977317,8823483334242,79413454477873, 714729551160822,6432599932896349, 57893535673021290] |