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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 12 |
| 5 | 30 |
| 6 | 80 |
| 7 | 236 |
| 8 | 782 |
| 9 | 2872 |
| 10 | 11551 |
| 11 | 50208 |
| 12 | 233475 |
| 13 | 1153424 |
| 14 | 6022129 |
| 15 | 33094892 |
| 16 | 190798443 |
| 17 | 1150698311 |
| 18 | 7241821945 |
| 19 | 47455029775 |
| 20 | 323155438297 |
| 21 | 2282781968327 |
| 22 | 16700909857189 |
| 23 | 126356647220803 |
| 24 | 987303496571557 |
| 25 | 7957134024398329 |
| 26 | 66071773173223712 |
[1,1,2,5,12,30,80,236,782,2872,11551,50208,233475, 1153424,6022129,33094892,190798443,1150698311, 7241821945,47455029775,323155438297,2282781968327, 16700909857189,126356647220803,987303496571557, 7957134024398329,66071773173223712] |