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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 120 |
| 3 | 4002 |
| 4 | 93500 |
| 5 | 1687002 |
| 6 | 24836196 |
| 7 | 309182762 |
| 8 | 3337508646 |
| 9 | 31830097752 |
| 10 | 272125000774 |
| 11 | 2109875558208 |
| 12 | 14977318285254 |
| 13 | 98118326104708 |
| 14 | 597217934730774 |
| 15 | 3397036441760412 |
| 16 | 18148572883826236 |
| 17 | 91470993083858322 |
| 18 | 436643312483178036 |
| 19 | 1981038544180652162 |
[2,120,4002,93500,1687002,24836196,309182762, 3337508646,31830097752,272125000774,2109875558208, 14977318285254,98118326104708,597217934730774, 3397036441760412,18148572883826236, 91470993083858322,436643312483178036, 1981038544180652162] |