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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 11 |
| 3 | 44 |
| 4 | 145 |
| 5 | 431 |
| 6 | 1216 |
| 7 | 3329 |
| 8 | 8955 |
| 9 | 23836 |
| 10 | 63041 |
| 11 | 166079 |
| 12 | 436480 |
| 13 | 1145441 |
| 14 | 3003211 |
| 15 | 7869644 |
| 16 | 20614545 |
| 17 | 53988271 |
| 18 | 141373376 |
| 19 | 370169249 |
| 20 | 969194875 |
| 21 | 2537513276 |
| 22 | 6643503361 |
| 23 | 17393253119 |
| 24 | 45536670720 |
| 25 | 119217430081 |
[1,11,44,145,431,1216,3329,8955,23836,63041, 166079,436480,1145441,3003211,7869644,20614545, 53988271,141373376,370169249,969194875,2537513276, 6643503361,17393253119,45536670720,119217430081] |