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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 2 |
| 4 | 4 |
| 5 | 5 |
| 6 | 18 |
| 7 | 30 |
| 8 | 94 |
| 9 | 226 |
| 10 | 715 |
| 11 | 2024 |
| 12 | 6546 |
| 13 | 20622 |
| 14 | 69459 |
| 15 | 232406 |
| 16 | 810943 |
| 17 | 2828246 |
[1,1,2,2,4,5,18,30,94,226,715,2024,6546,20622, 69459,232406,810943,2828246] |