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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 13 |
| 3 | 70 |
| 4 | 467 |
| 5 | 3224 |
| 6 | 23218 |
| 7 | 170155 |
| 8 | 1264605 |
| 9 | 9488108 |
| 10 | 71718240 |
| 11 | 545264052 |
| 12 | 4165262662 |
| 13 | 31943452900 |
| 14 | 245786167555 |
| 15 | 1896529843618 |
| 16 | 14669730799547 |
| 17 | 113713016901442 |
| 18 | 883107039574428 |
| 19 | 6869733556332042 |
| 20 | 53519589494550372 |
[3,13,70,467,3224,23218,170155,1264605,9488108, 71718240,545264052,4165262662,31943452900, 245786167555,1896529843618,14669730799547, 113713016901442,883107039574428,6869733556332042, 53519589494550372] |