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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 9 |
| 4 | 45 |
| 5 | 109 |
| 6 | 497 |
| 7 | 1505 |
| 8 | 6277 |
| 9 | 21933 |
| 10 | 87881 |
| 11 | 327701 |
| 12 | 1317185 |
| 13 | 5003189 |
| 14 | 20502937 |
| 15 | 78367049 |
| 16 | 325943661 |
| 17 | 1259386365 |
| 18 | 5266016649 |
| 19 | 20655292081 |
| 20 | 86435272421 |
| 21 | 343588605953 |
| 22 | 1439975562709 |
| 23 | 5775301253901 |
| 24 | 24286476447881 |
| 25 | 97980723577541 |
| 26 | 413563223119177 |
| 27 | 1677143349827301 |
| 28 | 7098191690374505 |
[1,1,5,9,45,109,497,1505,6277,21933,87881,327701, 1317185,5003189,20502937,78367049,325943661, 1259386365,5266016649,20655292081,86435272421, 343588605953,1439975562709,5775301253901, 24286476447881,97980723577541,413563223119177, 1677143349827301,7098191690374505] |