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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 3 |
| 3 | 8 |
| 4 | 24 |
| 5 | 73 |
| 6 | 230 |
| 7 | 751 |
| 8 | 2512 |
| 9 | 8549 |
| 10 | 29520 |
| 11 | 103192 |
| 12 | 364441 |
| 13 | 1298336 |
| 14 | 4660273 |
| 15 | 16837743 |
| 16 | 61187249 |
| 17 | 223489715 |
| 18 | 820040293 |
| 19 | 3021286338 |
| 20 | 11172619317 |
| 21 | 41454901924 |
| 22 | 154285693649 |
| 23 | 575826677260 |
| 24 | 2154643706124 |
| 25 | 8081453618583 |
| 26 | 30377809192246 |
| 27 | 114421431917805 |
[1,2,3,8,24,73,230,751,2512,8549,29520,103192, 364441,1298336,4660273,16837743,61187249, 223489715,820040293,3021286338,11172619317, 41454901924,154285693649,575826677260, 2154643706124,8081453618583,30377809192246, 114421431917805] |