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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 274 |
| 3 | 13195 |
| 4 | 191050 |
| 5 | 1558365 |
| 6 | 8335997 |
| 7 | 35065504 |
| 8 | 119156248 |
| 9 | 351839972 |
| 10 | 919946902 |
| 11 | 2202536367 |
| 12 | 4849690150 |
| 13 | 10068991557 |
| 14 | 19723016059 |
| 15 | 36893238627 |
| 16 | 66203565136 |
| 17 | 114800265705 |
| 18 | 192455268439 |
| 19 | 314206446033 |
| 20 | 499409248793 |
[1,274,13195,191050,1558365,8335997,35065504, 119156248,351839972,919946902,2202536367, 4849690150,10068991557,19723016059,36893238627, 66203565136,114800265705,192455268439, 314206446033,499409248793] |