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| n | a(n) |
|---|---|
| 1 | 13 |
| 2 | 106 |
| 3 | 948 |
| 4 | 8271 |
| 5 | 72745 |
| 6 | 638779 |
| 7 | 5611444 |
| 8 | 49287776 |
| 9 | 432936397 |
| 10 | 3802804497 |
| 11 | 33402966717 |
| 12 | 293403800602 |
| 13 | 2577190667088 |
| 14 | 22637440972719 |
| 15 | 198841998745267 |
| 16 | 1746581705515965 |
| 17 | 15341566059588032 |
| 18 | 134756735569827292 |
[13,106,948,8271,72745,638779,5611444,49287776, 432936397,3802804497,33402966717,293403800602, 2577190667088,22637440972719,198841998745267, 1746581705515965,15341566059588032, 134756735569827292] |