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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 10 |
| 4 | 37 |
| 5 | 186 |
| 6 | 931 |
| 7 | 5608 |
| 8 | 36345 |
| 9 | 252892 |
| 10 | 1961011 |
| 11 | 15811896 |
| 12 | 139137373 |
| 13 | 1286591320 |
| 14 | 12584565267 |
| 15 | 130564271776 |
| 16 | 1410581283121 |
| 17 | 16095825151248 |
| 18 | 190917669584035 |
| 19 | 2366869021623712 |
| 20 | 30550349329738581 |
| 21 | 408806590130340256 |
| 22 | 5688859328729212483 |
[1,1,3,10,37,186,931,5608,36345,252892,1961011, 15811896,139137373,1286591320,12584565267, 130564271776,1410581283121,16095825151248, 190917669584035,2366869021623712, 30550349329738581,408806590130340256, 5688859328729212483] |