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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 5 |
| 5 | 70 |
| 6 | 440 |
| 7 | 1055 |
| 8 | 1058 |
| 9 | 6461 |
| 10 | 6466 |
| 11 | 6469 |
| 12 | 251752 |
| 13 | 4124468 |
| 14 | 27067036 |
| 15 | 27067112 |
| 16 | 69709709 |
| 17 | 69709957 |
| 18 | 465769835 |
| 19 | 8179002104 |
| 20 | 145935689357 |
| 21 | 382465573490 |
[1,2,4,5,70,440,1055,1058,6461,6466,6469,251752, 4124468,27067036,27067112,69709709,69709957, 465769835,8179002104,145935689357,382465573490] |