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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 11 |
| 3 | 31 |
| 4 | 151 |
| 5 | 561 |
| 6 | 2361 |
| 7 | 9361 |
| 8 | 38171 |
| 9 | 153591 |
| 10 | 621911 |
| 11 | 2510721 |
| 12 | 10150321 |
| 13 | 41008321 |
| 14 | 165729931 |
| 15 | 669676751 |
| 16 | 2706201271 |
| 17 | 10935546481 |
| 18 | 44190379881 |
| 19 | 178571332881 |
| 20 | 721601251291 |
| 21 | 2915963545511 |
| 22 | 11783308434231 |
| 23 | 47615926483841 |
[1,11,31,151,561,2361,9361,38171,153591,621911, 2510721,10150321,41008321,165729931,669676751, 2706201271,10935546481,44190379881,178571332881, 721601251291,2915963545511,11783308434231, 47615926483841] |