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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 11 |
| 4 | 96 |
| 5 | 751 |
| 6 | 5531 |
| 7 | 39186 |
| 8 | 270241 |
| 9 | 1827071 |
| 10 | 12166176 |
| 11 | 80043931 |
| 12 | 521516711 |
| 13 | 3370600266 |
| 14 | 21637367221 |
| 15 | 138100531451 |
| 16 | 877053657456 |
| 17 | 5545955929111 |
| 18 | 34936157840291 |
| 19 | 219337228291746 |
| 20 | 1372926887328601 |
| 21 | 8570680318112231 |
| 22 | 53374194467267136 |
| 23 | 331661324567274691 |
[0,0,1,11,96,751,5531,39186,270241,1827071, 12166176,80043931,521516711,3370600266, 21637367221,138100531451,877053657456, 5545955929111,34936157840291,219337228291746, 1372926887328601,8570680318112231, 53374194467267136,331661324567274691] |