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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 11 |
| 3 | 101 |
| 4 | 491 |
| 5 | 3141 |
| 6 | 19301 |
| 7 | 115761 |
| 8 | 706591 |
| 9 | 4292223 |
| 10 | 26065517 |
| 11 | 158426129 |
| 12 | 962553071 |
| 13 | 5848496923 |
| 14 | 35536745667 |
| 15 | 215924096065 |
| 16 | 1311980244395 |
| 17 | 7971749802937 |
| 18 | 48437255764809 |
| 19 | 294310402140129 |
| 20 | 1788264132674883 |
[1,11,101,491,3141,19301,115761,706591,4292223, 26065517,158426129,962553071,5848496923, 35536745667,215924096065,1311980244395, 7971749802937,48437255764809,294310402140129, 1788264132674883] |