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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 13 |
| 2 | 157 |
| 3 | 1825 |
| 4 | 20761 |
| 5 | 233173 |
| 6 | 2598517 |
| 7 | 28818985 |
| 8 | 318655921 |
| 9 | 3516744733 |
| 10 | 38764899277 |
| 11 | 426978842545 |
| 12 | 4700721921481 |
| 13 | 51735623710693 |
| 14 | 569285638838437 |
| 15 | 6263498473368505 |
| 16 | 68907978330073441 |
| 17 | 758054227491947053 |
| 18 | 8339061763439391997 |
| 19 | 91732936225029132865 |
| 20 | 1009085096265691207801 |
[1,13,157,1825,20761,233173,2598517,28818985, 318655921,3516744733,38764899277,426978842545, 4700721921481,51735623710693,569285638838437, 6263498473368505,68907978330073441, 758054227491947053,8339061763439391997, 91732936225029132865,1009085096265691207801] |