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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 24 |
| 3 | 89 |
| 4 | 297 |
| 5 | 1145 |
| 6 | 4461 |
| 7 | 17661 |
| 8 | 70037 |
| 9 | 278116 |
| 10 | 1105688 |
| 11 | 4386052 |
| 12 | 17391896 |
| 13 | 68794424 |
| 14 | 272505548 |
| 15 | 1086983752 |
[1,5,24,89,297,1145,4461,17661,70037,278116, 1105688,4386052,17391896,68794424,272505548, 1086983752] |