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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 30 |
| 3 | 277 |
| 4 | 2349 |
| 5 | 19561 |
| 6 | 165010 |
| 7 | 1392131 |
| 8 | 11741731 |
| 9 | 99032014 |
| 10 | 835272398 |
| 11 | 7045026710 |
| 12 | 59420627072 |
| 13 | 501178143148 |
| 14 | 4227144439913 |
| 15 | 35653491957422 |
| 16 | 300716364726693 |
| 17 | 2536366776713612 |
| 18 | 21392771375921024 |
| 19 | 180435523636242529 |
[2,30,277,2349,19561,165010,1392131,11741731, 99032014,835272398,7045026710,59420627072, 501178143148,4227144439913,35653491957422, 300716364726693,2536366776713612, 21392771375921024,180435523636242529] |