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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 13 |
| 2 | 123 |
| 3 | 1037 |
| 4 | 8291 |
| 5 | 64509 |
| 6 | 494595 |
| 7 | 3761661 |
| 8 | 28486659 |
| 9 | 215277565 |
| 10 | 1625688067 |
| 11 | 12277764093 |
| 12 | 92783468547 |
| 13 | 701828038653 |
| 14 | 5314762113027 |
| 15 | 40297495658493 |
| 16 | 305941006516227 |
| 17 | 2325794003091453 |
| 18 | 17704219384479747 |
[1,13,123,1037,8291,64509,494595,3761661,28486659, 215277565,1625688067,12277764093,92783468547, 701828038653,5314762113027,40297495658493, 305941006516227,2325794003091453, 17704219384479747] |