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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 7 |
| 5 | 22 |
| 6 | 82 |
| 7 | 339 |
| 8 | 1505 |
| 9 | 7036 |
| 10 | 33836 |
| 11 | 166246 |
| 12 | 829987 |
| 13 | 4197273 |
| 14 | 21456444 |
| 15 | 110716585 |
| 16 | 576027737 |
| 17 | 3018986040 |
| 18 | 15927330105 |
| 19 | 84530870455 |
| 20 | 451069339063 |
| 21 | 2418927725532 |
| 22 | 13030938290472 |
| 23 | 70492771581350 |
| 24 | 382816374644336 |
| 25 | 2086362209298079 |
| 26 | 11408580755666756 |
[1,1,3,7,22,82,339,1505,7036,33836,166246,829987, 4197273,21456444,110716585,576027737,3018986040, 15927330105,84530870455,451069339063, 2418927725532,13030938290472,70492771581350, 382816374644336,2086362209298079, 11408580755666756] |