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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 1 |
| 9 | 4 |
| 10 | 7 |
| 11 | 14 |
| 12 | 21 |
| 13 | 51 |
| 14 | 123 |
| 15 | 453 |
| 16 | 1219 |
| 17 | 4641 |
| 18 | 13599 |
| 19 | 63683 |
| 20 | 242234 |
| 21 | 1440301 |
| 22 | 6546459 |
| 23 | 44699492 |
| 24 | 239296946 |
| 25 | 1977082524 |
| 26 | 12922743339 |
| 27 | 130202512826 |
| 28 | 1020385455911 |
| 29 | 12242346882334 |
[1,1,1,1,1,1,1,1,4,7,14,21,51,123,453,1219,4641, 13599,63683,242234,1440301,6546459,44699492, 239296946,1977082524,12922743339,130202512826, 1020385455911,12242346882334] |