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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 3 |
| 3 | 31 |
| 4 | 675 |
| 5 | 25231 |
| 6 | 1441923 |
| 7 | 116914351 |
| 8 | 12764590275 |
| 9 | 1805409270031 |
| 10 | 321113303226243 |
| 11 | 70146437009397871 |
| 12 | 18462286083671614275 |
| 13 | 5762225835975165678031 |
| 14 | 2104263061425865873128963 |
| 15 | 888881838896989670838028591 |
| 16 | 430058409024841744606172532675 |
[0,1,3,31,675,25231,1441923,116914351,12764590275, 1805409270031,321113303226243,70146437009397871, 18462286083671614275,5762225835975165678031, 2104263061425865873128963, 888881838896989670838028591, 430058409024841744606172532675] |