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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 3 |
| 3 | 4 |
| 4 | 5 |
| 5 | 10 |
| 6 | 23 |
| 7 | 56 |
| 8 | 141 |
| 9 | 366 |
| 10 | 955 |
| 11 | 2496 |
| 12 | 6529 |
| 13 | 17090 |
| 14 | 44739 |
| 15 | 117124 |
| 16 | 306629 |
| 17 | 802762 |
| 18 | 2101655 |
| 19 | 5502200 |
| 20 | 14404941 |
| 21 | 37712622 |
| 22 | 98732923 |
| 23 | 258486144 |
| 24 | 676725505 |
| 25 | 1771690370 |
| 26 | 4638345603 |
| 27 | 12143346436 |
| 28 | 31791693701 |
| 29 | 83231734666 |
| 30 | 217903510295 |
[1,2,3,4,5,10,23,56,141,366,955,2496,6529,17090, 44739,117124,306629,802762,2101655,5502200, 14404941,37712622,98732923,258486144,676725505, 1771690370,4638345603,12143346436,31791693701, 83231734666,217903510295] |