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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 5 |
| 4 | 13 |
| 5 | 77 |
| 6 | 29 |
| 7 | 223 |
| 8 | 481 |
| 9 | 4609 |
| 10 | 4861 |
| 11 | 55991 |
| 12 | 58301 |
| 13 | 785633 |
| 14 | 811373 |
| 15 | 835397 |
| 16 | 1715839 |
| 17 | 29889983 |
| 18 | 10190221 |
| 19 | 197698279 |
| 20 | 40315631 |
| 21 | 13684885 |
| 22 | 13920029 |
| 23 | 325333835 |
| 24 | 990874363 |
| 25 | 25128807667 |
| 26 | 25472027467 |
| 27 | 232222818803 |
| 28 | 235091155703 |
| 29 | 6897956948587 |
| 30 | 6975593267347 |
[0,1,5,13,77,29,223,481,4609,4861,55991,58301, 785633,811373,835397,1715839,29889983,10190221, 197698279,40315631,13684885,13920029,325333835, 990874363,25128807667,25472027467,232222818803, 235091155703,6897956948587,6975593267347] |