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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 19 |
| 8 | 31 |
| 9 | 655 |
| 10 | 1339 |
| 11 | 18309 |
| 12 | 48007 |
| 13 | 1442201 |
| 14 | 4567021 |
| 15 | 367217353 |
| 16 | 1460020323 |
| 17 | 228615404039 |
| 18 | 1133359885719 |
| 19 | 280150745688529 |
| 20 | 1717585325345099 |
| 21 | 785288102542995777 |
| 22 | 5945777223826707809 |
[1,1,1,1,1,1,19,31,655,1339,18309,48007,1442201, 4567021,367217353,1460020323,228615404039, 1133359885719,280150745688529,1717585325345099, 785288102542995777,5945777223826707809] |