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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 1 |
| 9 | 5 |
| 10 | 13 |
| 11 | 25 |
| 12 | 41 |
| 13 | 107 |
| 14 | 335 |
| 15 | 953 |
| 16 | 3255 |
| 17 | 14559 |
| 18 | 66659 |
| 19 | 322289 |
| 20 | 1582731 |
| 21 | 8865325 |
| 22 | 55810029 |
[1,1,1,1,1,1,1,1,5,13,25,41,107,335,953,3255, 14559,66659,322289,1582731,8865325,55810029] |