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| n | a(n) |
|---|---|
| 9 | 1 |
| 10 | 1 |
| 11 | 6 |
| 12 | 30 |
| 13 | 127 |
| 14 | 506 |
| 15 | 1902 |
| 16 | 6823 |
| 17 | 23673 |
| 18 | 79936 |
| 19 | 264036 |
| 20 | 856772 |
| 21 | 2739525 |
| 22 | 8652707 |
| 23 | 27049259 |
| 24 | 83824636 |
| 25 | 257847515 |
| 26 | 788121922 |
| 27 | 2395786374 |
| 28 | 7248517868 |
| 29 | 21840785100 |
| 30 | 65574504200 |
| 31 | 196266067194 |
| 32 | 585822825763 |
| 33 | 1744384025528 |
| 34 | 5183186173513 |
| 35 | 15372268502463 |
| 36 | 45515472900289 |
[1,1,6,30,127,506,1902,6823,23673,79936,264036, 856772,2739525,8652707,27049259,83824636, 257847515,788121922,2395786374,7248517868, 21840785100,65574504200,196266067194,585822825763, 1744384025528,5183186173513,15372268502463, 45515472900289] |