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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 16 |
| 5 | 45 |
| 6 | 139 |
| 7 | 469 |
| 8 | 1658 |
| 9 | 5609 |
| 10 | 19819 |
| 11 | 72907 |
| 12 | 273302 |
| 13 | 1001029 |
| 14 | 3764252 |
| 15 | 14482663 |
| 16 | 56301014 |
| 17 | 215614487 |
| 18 | 840666091 |
| 19 | 3327207607 |
| 20 | 13256846148 |
| 21 | 52244731775 |
| 22 | 208630339806 |
| 23 | 842156982607 |
| 24 | 3415588505022 |
| 25 | 13733348825741 |
| 26 | 55789315174791 |
| 27 | 228512108471269 |
| 28 | 939317595835978 |
| 29 | 3833421230019903 |
[1,1,2,5,16,45,139,469,1658,5609,19819,72907, 273302,1001029,3764252,14482663,56301014, 215614487,840666091,3327207607,13256846148, 52244731775,208630339806,842156982607, 3415588505022,13733348825741,55789315174791, 228512108471269,939317595835978,3833421230019903] |