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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 15 |
| 5 | 30 |
| 6 | 59 |
| 7 | 114 |
| 8 | 219 |
| 9 | 416 |
| 10 | 783 |
| 11 | 1461 |
| 12 | 2722 |
| 13 | 5048 |
| 14 | 9341 |
| 15 | 17243 |
| 16 | 31674 |
| 17 | 58037 |
| 18 | 105936 |
| 19 | 192522 |
| 20 | 348832 |
[1,3,7,15,30,59,114,219,416,783,1461,2722,5048, 9341,17243,31674,58037,105936,192522,348832] |