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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 4 |
| 6 | 5 |
| 7 | 29 |
| 8 | 133 |
| 9 | 412 |
| 10 | 1041 |
| 11 | 2300 |
| 12 | 22991 |
| 13 | 170832 |
| 14 | 822198 |
| 15 | 3114489 |
| 16 | 10006375 |
| 17 | 141705439 |
| 18 | 1457872978 |
| 19 | 9522474417 |
| 20 | 48094772656 |
| 21 | 202808749375 |
| 22 | 3716808948931 |
| 23 | 48860589990687 |
| 24 | 403131250565618 |
| 25 | 2545098156762649 |
| 26 | 13287626090593750 |
[1,1,1,2,3,4,5,29,133,412,1041,2300,22991,170832, 822198,3114489,10006375,141705439,1457872978, 9522474417,48094772656,202808749375,3716808948931, 48860589990687,403131250565618,2545098156762649, 13287626090593750] |