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| n | a(n) |
|---|---|
| 1 | 13 |
| 2 | 73 |
| 3 | 59 |
| 4 | 518 |
| 5 | 4320 |
| 6 | 18775 |
| 7 | 153289 |
| 8 | 1162345 |
| 9 | 7133776 |
| 10 | 54979586 |
| 11 | 402166114 |
| 12 | 2748707739 |
| 13 | 20339364130 |
| 14 | 147487006730 |
| 15 | 1043506098401 |
| 16 | 7599112187024 |
| 17 | 54923304977846 |
| 18 | 393412536966095 |
| 19 | 2847592555411713 |
| 20 | 20556758995325968 |
[13,73,59,518,4320,18775,153289,1162345,7133776, 54979586,402166114,2748707739,20339364130, 147487006730,1043506098401,7599112187024, 54923304977846,393412536966095,2847592555411713, 20556758995325968] |