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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 9 |
| 2 | 118 |
| 3 | 1773 |
| 4 | 28650 |
| 5 | 484578 |
| 6 | 8457708 |
| 7 | 151054173 |
| 8 | 2745685954 |
| 9 | 50606020854 |
| 10 | 943283037684 |
| 11 | 17746990547634 |
| 12 | 336517405188900 |
| 13 | 6423775409047716 |
| 14 | 123332141503711704 |
| 15 | 2379824766494404317 |
| 16 | 46124764901514110898 |
| 17 | 897483137740689843054 |
| 18 | 17524230350476917414180 |
[1,9,118,1773,28650,484578,8457708,151054173, 2745685954,50606020854,943283037684, 17746990547634,336517405188900,6423775409047716, 123332141503711704,2379824766494404317, 46124764901514110898,897483137740689843054, 17524230350476917414180] |