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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 5 |
| 9 | 13 |
| 10 | 25 |
| 11 | 41 |
| 12 | 73 |
| 13 | 405 |
| 14 | 2087 |
| 15 | 9095 |
| 16 | 31781 |
| 17 | 109905 |
| 18 | 706437 |
| 19 | 6193961 |
| 20 | 52066515 |
| 21 | 395176419 |
| 22 | 2801856537 |
| 23 | 27230658787 |
[1,1,1,1,1,1,1,5,13,25,41,73,405,2087,9095,31781, 109905,706437,6193961,52066515,395176419, 2801856537,27230658787] |