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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 3 |
| 7 | 5 |
| 8 | 11 |
| 9 | 21 |
| 10 | 41 |
| 11 | 165 |
| 12 | 701 |
| 13 | 2953 |
| 14 | 12345 |
| 15 | 51325 |
| 16 | 344201 |
| 17 | 2572877 |
| 18 | 21631323 |
| 19 | 180106811 |
| 20 | 1718811817 |
| 21 | 19639803327 |
| 22 | 281005626019 |
| 23 | 4302161174593 |
| 24 | 75232261306781 |
| 25 | 1397819874484453 |
| 26 | 32083258430460691 |
[1,1,1,1,1,3,5,11,21,41,165,701,2953,12345,51325, 344201,2572877,21631323,180106811,1718811817, 19639803327,281005626019,4302161174593, 75232261306781,1397819874484453,32083258430460691] |