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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 11 |
| 3 | 88 |
| 4 | 869 |
| 5 | 9876 |
| 6 | 124473 |
| 7 | 1701630 |
| 8 | 24870695 |
| 9 | 384795184 |
| 10 | 6257294780 |
| 11 | 106377162620 |
| 12 | 1882982975521 |
| 13 | 34593496243070 |
| 14 | 657935674477431 |
| 15 | 12927331575084846 |
| 16 | 261951066040220637 |
| 17 | 5466177185459699916 |
| 18 | 117315664923801661485 |
| 19 | 2586804284853871362408 |
[1,2,11,88,869,9876,124473,1701630,24870695, 384795184,6257294780,106377162620,1882982975521, 34593496243070,657935674477431,12927331575084846, 261951066040220637,5466177185459699916, 117315664923801661485,2586804284853871362408] |