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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 9 |
| 5 | 21 |
| 6 | 61 |
| 7 | 211 |
| 8 | 673 |
| 9 | 1849 |
| 10 | 4441 |
| 11 | 9571 |
| 12 | 18921 |
| 13 | 34893 |
| 14 | 60789 |
| 15 | 101011 |
| 16 | 161281 |
| 17 | 248881 |
| 18 | 372913 |
| 19 | 544579 |
| 20 | 777481 |
| 21 | 1087941 |
| 22 | 1495341 |
| 23 | 2022483 |
| 24 | 2695969 |
| 25 | 3546601 |
| 26 | 4609801 |
| 27 | 5926051 |
| 28 | 7541353 |
| 29 | 9507709 |
| 30 | 11883621 |
| 31 | 14734611 |
| 32 | 18133761 |
| 33 | 22162273 |
| 34 | 26910049 |
| 35 | 32476291 |
[1,1,1,3,9,21,61,211,673,1849,4441,9571,18921, 34893,60789,101011,161281,248881,372913,544579, 777481,1087941,1495341,2022483,2695969,3546601, 4609801,5926051,7541353,9507709,11883621,14734611, 18133761,22162273,26910049,32476291] |