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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 4 |
| 5 | 43 |
| 6 | 1156 |
| 7 | 74581 |
| 8 | 11226874 |
| 9 | 3862830343 |
| 10 | 2990426173816 |
| 11 | 5144550664291081 |
| 12 | 19470823356314891254 |
| 13 | 160782837107861606438923 |
| 14 | 2876650791540557329654540276 |
| 15 | 110853465572134076561454447710221 |
[1,1,1,4,43,1156,74581,11226874,3862830343, 2990426173816,5144550664291081, 19470823356314891254,160782837107861606438923, 2876650791540557329654540276, 110853465572134076561454447710221] |