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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 140 |
| 3 | 280 |
| 4 | 1092 |
| 5 | 166460 |
| 6 | 189070 |
| 7 | 665840 |
| 8 | 804540 |
| 9 | 845460 |
| 10 | 34250920 |
| 11 | 38336088 |
| 12 | 133784560 |
| 13 | 138535992 |
| 14 | 225792840 |
| 15 | 4998790160 |
| 16 | 6301258040 |
| 17 | 7559616818 |
| 18 | 8367691640 |
| 19 | 39991371446 |
| 20 | 104637102152 |
| 21 | 227490888350 |
| 22 | 1497809326860 |
| 23 | 296523233581822 |
[2,140,280,1092,166460,189070,665840,804540, 845460,34250920,38336088,133784560,138535992, 225792840,4998790160,6301258040,7559616818, 8367691640,39991371446,104637102152,227490888350, 1497809326860,296523233581822] |