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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 2 |
| 2 | 4 |
| 3 | 350 |
| 4 | 7208 |
| 5 | 1278298 |
| 6 | 79874540 |
| 7 | 24248146806 |
| 8 | 3094746649296 |
| 9 | 1450703467495218 |
| 10 | 311518889830786132 |
| 11 | 210537148539150077966 |
| 12 | 67821849231894539132920 |
| 13 | 62959878878133692157576586 |
[0,2,4,350,7208,1278298,79874540,24248146806, 3094746649296,1450703467495218,311518889830786132, 210537148539150077966,67821849231894539132920, 62959878878133692157576586] |