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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 30 |
| 5 | 113 |
| 6 | 472 |
| 7 | 2145 |
| 8 | 10514 |
| 9 | 55428 |
| 10 | 313255 |
| 11 | 1886888 |
| 12 | 12029741 |
| 13 | 80701715 |
| 14 | 567541878 |
| 15 | 4175795147 |
| 16 | 32104799401 |
| 17 | 257561662496 |
| 18 | 2151841672173 |
| 19 | 18676002357864 |
| 20 | 167951667633495 |
| 21 | 1561420657033927 |
| 22 | 14980472336450530 |
| 23 | 148140814019762129 |
| 24 | 1508776236781766431 |
[1,3,9,30,113,472,2145,10514,55428,313255,1886888, 12029741,80701715,567541878,4175795147, 32104799401,257561662496,2151841672173, 18676002357864,167951667633495,1561420657033927, 14980472336450530,148140814019762129, 1508776236781766431] |