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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 4 |
| 4 | 75 |
| 5 | 7636 |
| 6 | 4866965 |
| 7 | 22256484426 |
| 8 | 827473662052359 |
| 9 | 280073424855627741304 |
| 10 | 956136927041635596586248969 |
| 11 | 36146438316110599447497305174316790 |
| 12 | 16486165931975571004114967909531846539984907 |
[1,1,1,4,75,7636,4866965,22256484426, 827473662052359,280073424855627741304, 956136927041635596586248969, 36146438316110599447497305174316790, 16486165931975571004114967909531846539984907] |