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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 13 |
| 3 | 333 |
| 4 | 10712 |
| 5 | 400075 |
| 6 | 16435017 |
| 7 | 721861385 |
| 8 | 33308540000 |
| 9 | 1596292110000 |
| 10 | 78832566399375 |
| 11 | 3989172320345245 |
| 12 | 205979496842877048 |
| 13 | 10817872108002076923 |
| 14 | 576440295110730997877 |
| 15 | 31102930647624990624975 |
[1,13,333,10712,400075,16435017,721861385, 33308540000,1596292110000,78832566399375, 3989172320345245,205979496842877048, 10817872108002076923,576440295110730997877, 31102930647624990624975] |