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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 6 |
| 5 | 11 |
| 6 | 23 |
| 7 | 43 |
| 8 | 93 |
| 9 | 181 |
| 10 | 392 |
| 11 | 783 |
| 12 | 1710 |
| 13 | 3467 |
| 14 | 7623 |
| 15 | 15655 |
| 16 | 34543 |
| 17 | 71688 |
| 18 | 158721 |
| 19 | 332006 |
| 20 | 737213 |
| 21 | 1552365 |
| 22 | 3455004 |
| 23 | 7315948 |
| 24 | 16315297 |
| 25 | 34711474 |
| 26 | 77544359 |
| 27 | 165653643 |
| 28 | 370623055 |
[1,2,3,6,11,23,43,93,181,392,783,1710,3467,7623, 15655,34543,71688,158721,332006,737213,1552365, 3455004,7315948,16315297,34711474,77544359, 165653643,370623055] |