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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 11 |
| 5 | 18 |
| 6 | 117 |
| 7 | 162 |
| 8 | 1205 |
| 9 | 3621 |
| 10 | 29271 |
| 11 | 68086 |
| 12 | 1069614 |
| 13 | 2305158 |
| 14 | 31825670 |
| 15 | 172974370 |
| 16 | 1311400891 |
| 17 | 5179123522 |
| 18 | 113680235941 |
| 19 | 324041807958 |
| 20 | 6466011855715 |
| 21 | 39572612670818 |
| 22 | 450671611457619 |
| 23 | 2006909406239780 |
| 24 | 55745145216877102 |
| 25 | 231929517217884081 |
[1,2,4,11,18,117,162,1205,3621,29271,68086, 1069614,2305158,31825670,172974370,1311400891, 5179123522,113680235941,324041807958, 6466011855715,39572612670818,450671611457619, 2006909406239780,55745145216877102, 231929517217884081] |