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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 10 |
| 3 | 105 |
| 4 | 1018 |
| 5 | 9157 |
| 6 | 77934 |
| 7 | 638065 |
| 8 | 5084818 |
| 9 | 39762621 |
| 10 | 306822358 |
| 11 | 2345284009 |
| 12 | 17806600698 |
| 13 | 134548145461 |
| 14 | 1013159874046 |
| 15 | 7610346917985 |
| 16 | 57063648570850 |
| 17 | 427326717363757 |
| 18 | 3197140079770278 |
| 19 | 23904313586774425 |
| 20 | 178642318573382986 |
[1,10,105,1018,9157,77934,638065,5084818,39762621, 306822358,2345284009,17806600698,134548145461, 1013159874046,7610346917985,57063648570850, 427326717363757,3197140079770278, 23904313586774425,178642318573382986] |