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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 9 |
| 3 | 161 |
| 4 | 4412 |
| 5 | 164024 |
| 6 | 7721898 |
| 7 | 440550102 |
| 8 | 29548655696 |
| 9 | 2278884869640 |
| 10 | 198709176600696 |
| 11 | 19331290511231280 |
| 12 | 2075887738522499664 |
| 13 | 243905626745780976144 |
| 14 | 31125204862136659763040 |
| 15 | 4287017279890868817295728 |
| 16 | 633888142969750426274770944 |
[1,1,9,161,4412,164024,7721898,440550102, 29548655696,2278884869640,198709176600696, 19331290511231280,2075887738522499664, 243905626745780976144,31125204862136659763040, 4287017279890868817295728, 633888142969750426274770944] |