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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 29 |
| 5 | 97 |
| 6 | 333 |
| 7 | 1165 |
| 8 | 4135 |
| 9 | 14845 |
| 10 | 53791 |
| 11 | 196417 |
| 12 | 721887 |
| 13 | 2667941 |
| 14 | 9907851 |
| 15 | 36950465 |
| 16 | 138320021 |
| 17 | 519515209 |
| 18 | 1957091277 |
| 19 | 7392602917 |
| 20 | 27992976565 |
| 21 | 106236268337 |
| 22 | 404005515873 |
| 23 | 1539293204549 |
| 24 | 5875059106769 |
| 25 | 22459721336977 |
[1,1,3,9,29,97,333,1165,4135,14845,53791,196417, 721887,2667941,9907851,36950465,138320021, 519515209,1957091277,7392602917,27992976565, 106236268337,404005515873,1539293204549, 5875059106769,22459721336977] |