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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 5 |
| 6 | 17 |
| 7 | 44 |
| 8 | 182 |
| 9 | 730 |
| 10 | 4032 |
| 11 | 25598 |
| 12 | 212780 |
| 13 | 2241730 |
| 14 | 31193324 |
| 15 | 575252112 |
| 16 | 14218209962 |
| 17 | 472740425319 |
| 18 | 21208887576786 |
| 19 | 1286099113807999 |
| 20 | 105567921675718772 |
| 21 | 11743905783670560579 |
| 22 | 1772771666309380358809 |
| 23 | 363526952035325887859823 |
| 24 | 101386021137641794979558045 |
[1,1,1,1,3,5,17,44,182,730,4032,25598,212780, 2241730,31193324,575252112,14218209962, 472740425319,21208887576786,1286099113807999, 105567921675718772,11743905783670560579, 1772771666309380358809,363526952035325887859823, 101386021137641794979558045] |