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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 17 |
| 3 | 197 |
| 4 | 1985 |
| 5 | 18621 |
| 6 | 167337 |
| 7 | 1461797 |
| 8 | 12519345 |
| 9 | 105683341 |
| 10 | 882516857 |
| 11 | 7308428597 |
| 12 | 60131384705 |
| 13 | 492202181661 |
| 14 | 4012347269577 |
| 15 | 32599584662597 |
| 16 | 264152863210065 |
| 17 | 2135714594033581 |
| 18 | 17236446198921497 |
| 19 | 138901692341235797 |
| 20 | 1117982939085627425 |
| 21 | 8989229069675479101 |
[1,17,197,1985,18621,167337,1461797,12519345, 105683341,882516857,7308428597,60131384705, 492202181661,4012347269577,32599584662597, 264152863210065,2135714594033581, 17236446198921497,138901692341235797, 1117982939085627425,8989229069675479101] |