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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 9 |
| 3 | 31 |
| 4 | 107 |
| 5 | 501 |
| 6 | 2339 |
| 7 | 10303 |
| 8 | 44523 |
| 9 | 198695 |
| 10 | 888601 |
| 11 | 3941855 |
| 12 | 18017983 |
| 13 | 83483541 |
| 14 | 389450325 |
| 15 | 1838319253 |
| 16 | 8707491533 |
| 17 | 41316656737 |
| 18 | 196349474191 |
| 19 | 934444664373 |
| 20 | 4453775875859 |
| 21 | 21254863852755 |
| 22 | 101613183769703 |
| 23 | 486794625431383 |
[1,9,31,107,501,2339,10303,44523,198695,888601, 3941855,18017983,83483541,389450325,1838319253, 8707491533,41316656737,196349474191,934444664373, 4453775875859,21254863852755,101613183769703, 486794625431383] |