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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 21 |
| 3 | 73 |
| 4 | 229 |
| 5 | 1189 |
| 6 | 5637 |
| 7 | 25941 |
| 8 | 115997 |
| 9 | 490237 |
| 10 | 2006653 |
| 11 | 8111485 |
| 12 | 32609149 |
| 13 | 130756477 |
| 14 | 523659133 |
| 15 | 2095896445 |
[1,5,21,73,229,1189,5637,25941,115997,490237, 2006653,8111485,32609149,130756477,523659133, 2095896445] |