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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 13 |
| 3 | 123 |
| 4 | 1205 |
| 5 | 12287 |
| 6 | 135179 |
| 7 | 1493247 |
| 8 | 16814401 |
| 9 | 192346557 |
| 10 | 2225951035 |
| 11 | 26017190841 |
| 12 | 306761764259 |
| 13 | 3644115496927 |
| 14 | 43571997337907 |
| 15 | 523947428428811 |
| 16 | 6331638407455241 |
| 17 | 76845558853198515 |
| 18 | 936178097032511349 |
[1,13,123,1205,12287,135179,1493247,16814401, 192346557,2225951035,26017190841,306761764259, 3644115496927,43571997337907,523947428428811, 6331638407455241,76845558853198515, 936178097032511349] |