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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 33 |
| 3 | 107 |
| 4 | 287 |
| 5 | 2098 |
| 6 | 9344 |
| 7 | 35733 |
| 8 | 182881 |
| 9 | 859151 |
| 10 | 3752449 |
| 11 | 17718898 |
| 12 | 83133830 |
| 13 | 379861714 |
| 14 | 1768819146 |
| 15 | 8263436507 |
| 16 | 38298070989 |
| 17 | 178230046892 |
| 18 | 831322027550 |
| 19 | 3869744621937 |
| 20 | 18028069104813 |
| 21 | 84070919008122 |
| 22 | 391898815331194 |
[1,33,107,287,2098,9344,35733,182881,859151, 3752449,17718898,83133830,379861714,1768819146, 8263436507,38298070989,178230046892,831322027550, 3869744621937,18028069104813,84070919008122, 391898815331194] |