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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 5 |
| 7 | 13 |
| 8 | 32 |
| 9 | 116 |
| 10 | 329 |
| 11 | 1343 |
| 12 | 7578 |
| 13 | 43263 |
| 14 | 292424 |
| 15 | 2337772 |
| 16 | 20731810 |
| 17 | 226646472 |
| 18 | 2872512529 |
| 19 | 41869404152 |
| 20 | 707811350778 |
| 21 | 14078518669729 |
| 22 | 324770949354296 |
[1,1,1,1,1,5,13,32,116,329,1343,7578,43263,292424, 2337772,20731810,226646472,2872512529,41869404152, 707811350778,14078518669729,324770949354296] |