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| n | a(n) |
|---|---|
| 2 | 2 |
| 3 | 15 |
| 4 | 99 |
| 5 | 722 |
| 6 | 8410 |
| 7 | 123813 |
| 8 | 2177847 |
| 9 | 44317852 |
| 10 | 1023457869 |
| 11 | 26432595075 |
| 12 | 754777789018 |
| 13 | 23609224082310 |
| 14 | 802772380561983 |
| 15 | 29480883458980947 |
| 16 | 1162849439785414095 |
| 17 | 49030176097150565512 |
| 18 | 2200618769387073010719 |
| 19 | 104753196945250864019109 |
| 20 | 5271200265927977839358758 |
[2,15,99,722,8410,123813,2177847,44317852, 1023457869,26432595075,754777789018, 23609224082310,802772380561983,29480883458980947, 1162849439785414095,49030176097150565512, 2200618769387073010719,104753196945250864019109, 5271200265927977839358758] |