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| n | a(n) |
|---|---|
| 1 | 21 |
| 2 | 11 |
| 3 | 148 |
| 4 | 1822 |
| 5 | 31867 |
| 6 | 437276 |
| 7 | 6236246 |
| 8 | 88486037 |
| 9 | 1253495751 |
| 10 | 17820280071 |
| 11 | 252432128095 |
| 12 | 3581335862055 |
| 13 | 50810347370710 |
| 14 | 720844568426583 |
| 15 | 10226876364949089 |
| 16 | 145096143960674291 |
| 17 | 2058575118040453456 |
[21,11,148,1822,31867,437276,6236246,88486037, 1253495751,17820280071,252432128095,3581335862055, 50810347370710,720844568426583,10226876364949089, 145096143960674291,2058575118040453456] |