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| n | a(n) |
|---|---|
| 1 | 15 |
| 2 | 103 |
| 3 | 2399 |
| 4 | 43013 |
| 5 | 602498 |
| 6 | 7275277 |
| 7 | 80593130 |
| 8 | 831309835 |
| 9 | 7991092857 |
| 10 | 71939079266 |
| 11 | 610644584474 |
| 12 | 4918787099538 |
| 13 | 37785795751722 |
| 14 | 277933274570500 |
| 15 | 1964256584666302 |
| 16 | 13379033454664698 |
| 17 | 88056377306979930 |
| 18 | 561276655188818601 |
[15,103,2399,43013,602498,7275277,80593130, 831309835,7991092857,71939079266,610644584474, 4918787099538,37785795751722,277933274570500, 1964256584666302,13379033454664698, 88056377306979930,561276655188818601] |