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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 17 |
| 3 | 105 |
| 4 | 783 |
| 5 | 5622 |
| 6 | 40608 |
| 7 | 293084 |
| 8 | 2115379 |
| 9 | 15268366 |
| 10 | 110202874 |
| 11 | 795416273 |
| 12 | 5741108247 |
| 13 | 41437835079 |
| 14 | 299087573904 |
| 15 | 2158736742330 |
| 16 | 15581203397143 |
| 17 | 112461095655909 |
| 18 | 811715097631008 |
| 19 | 5858749604657939 |
| 20 | 42286939137094085 |
[1,17,105,783,5622,40608,293084,2115379,15268366, 110202874,795416273,5741108247,41437835079, 299087573904,2158736742330,15581203397143, 112461095655909,811715097631008,5858749604657939, 42286939137094085] |