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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 5 |
| 7 | 13 |
| 8 | 29 |
| 9 | 73 |
| 10 | 193 |
| 11 | 581 |
| 12 | 1717 |
| 13 | 7029 |
| 14 | 21981 |
| 15 | 79625 |
| 16 | 248697 |
| 17 | 981353 |
| 18 | 3275085 |
| 19 | 13235333 |
[1,1,1,1,1,5,13,29,73,193,581,1717,7029,21981, 79625,248697,981353,3275085,13235333] |