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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 32 |
| 5 | 115 |
| 6 | 442 |
| 7 | 1744 |
| 8 | 7051 |
| 9 | 29126 |
| 10 | 122239 |
| 11 | 519591 |
| 12 | 2234239 |
| 13 | 9694435 |
| 14 | 42403432 |
| 15 | 186764362 |
| 16 | 827508472 |
| 17 | 3686022642 |
| 18 | 16495984895 |
| 19 | 74131461638 |
| 20 | 334391209125 |
| 21 | 1513451195963 |
| 22 | 6870755524144 |
| 23 | 31278458876548 |
| 24 | 142752688871557 |
| 25 | 653025242118420 |
| 26 | 2993654192961094 |
| 27 | 13750770322469604 |
| 28 | 63276530783178980 |
[1,1,3,9,32,115,442,1744,7051,29126,122239,519591, 2234239,9694435,42403432,186764362,827508472, 3686022642,16495984895,74131461638,334391209125, 1513451195963,6870755524144,31278458876548, 142752688871557,653025242118420,2993654192961094, 13750770322469604,63276530783178980] |