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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 70 |
| 3 | 34650 |
| 4 | 63063000 |
| 5 | 142951955371 |
| 6 | 389426248416626 |
| 7 | 1238402046254860022 |
| 8 | 4454056622413300252928 |
| 9 | 17668055644599543583018570 |
| 10 | 75867559322054514745288107364 |
| 11 | 347785237467609520037269752908904 |
| 12 | 1684035818793607129226446293560872032 |
[1,1,70,34650,63063000,142951955371, 389426248416626,1238402046254860022, 4454056622413300252928,17668055644599543583018570, 75867559322054514745288107364, 347785237467609520037269752908904, 1684035818793607129226446293560872032] |