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| n | a(n) |
|---|---|
| 1 | 13 |
| 2 | 169 |
| 3 | 677 |
| 4 | 4219 |
| 5 | 21517 |
| 6 | 119965 |
| 7 | 644401 |
| 8 | 3523073 |
| 9 | 19109897 |
| 10 | 103977527 |
| 11 | 564853957 |
| 12 | 3070715725 |
| 13 | 16689263845 |
| 14 | 90719255481 |
| 15 | 493099242743 |
| 16 | 2680257849413 |
| 17 | 14568413911287 |
| 18 | 79186365292369 |
| 19 | 430415795271435 |
| 20 | 2339519840411823 |
[13,169,677,4219,21517,119965,644401,3523073, 19109897,103977527,564853957,3070715725, 16689263845,90719255481,493099242743, 2680257849413,14568413911287,79186365292369, 430415795271435,2339519840411823] |