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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 9 |
| 5 | 19 |
| 6 | 49 |
| 7 | 100 |
| 8 | 233 |
| 9 | 503 |
| 10 | 1166 |
| 11 | 2580 |
| 12 | 5884 |
| 13 | 13092 |
| 14 | 29622 |
| 15 | 66281 |
| 16 | 149569 |
| 17 | 335524 |
| 18 | 755737 |
| 19 | 1697149 |
| 20 | 3819301 |
| 21 | 8582469 |
| 22 | 19306314 |
| 23 | 43397191 |
| 24 | 97600441 |
| 25 | 219421360 |
| 26 | 493425528 |
| 27 | 1109386496 |
| 28 | 2494606984 |
| 29 | 5608933040 |
| 30 | 12612101201 |
[1,1,2,3,9,19,49,100,233,503,1166,2580,5884,13092, 29622,66281,149569,335524,755737,1697149,3819301, 8582469,19306314,43397191,97600441,219421360, 493425528,1109386496,2494606984,5608933040, 12612101201] |