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| n | a(n) |
|---|---|
| 1 | 13 |
| 2 | 148 |
| 3 | 1977 |
| 4 | 27720 |
| 5 | 393649 |
| 6 | 5608216 |
| 7 | 79963353 |
| 8 | 1140367704 |
| 9 | 16263750913 |
| 10 | 231954064216 |
| 11 | 3308145663081 |
| 12 | 47181050078808 |
| 13 | 672900213492241 |
| 14 | 9596961465020248 |
| 15 | 136872702133795833 |
| 16 | 1952090431423132248 |
[13,148,1977,27720,393649,5608216,79963353, 1140367704,16263750913,231954064216,3308145663081, 47181050078808,672900213492241,9596961465020248, 136872702133795833,1952090431423132248] |