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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 4 |
| 2 | 44 |
| 3 | 1912 |
| 4 | 156816 |
| 5 | 21506816 |
| 6 | 4420845376 |
| 7 | 1271132964480 |
| 8 | 487161448339712 |
| 9 | 239980527068474368 |
| 10 | 147742478026391141376 |
| 11 | 111153314734461183924224 |
| 12 | 100339775128577885016985600 |
| 13 | 107037870347952811373977239552 |
| 14 | 133204585741561810426003651444736 |
[1,4,44,1912,156816,21506816,4420845376, 1271132964480,487161448339712,239980527068474368, 147742478026391141376,111153314734461183924224, 100339775128577885016985600, 107037870347952811373977239552, 133204585741561810426003651444736] |