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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 11 |
| 5 | 23 |
| 6 | 48 |
| 7 | 85 |
| 8 | 178 |
| 9 | 331 |
| 10 | 619 |
| 11 | 1176 |
| 12 | 2183 |
| 13 | 3876 |
| 14 | 7013 |
| 15 | 12447 |
| 16 | 21719 |
| 17 | 37628 |
| 18 | 64570 |
| 19 | 109723 |
| 20 | 185055 |
[1,3,6,11,23,48,85,178,331,619,1176,2183,3876, 7013,12447,21719,37628,64570,109723,185055] |