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| n | a(n) |
|---|---|
| 0 | 13 |
| 1 | 27 |
| 2 | 67 |
| 3 | 161 |
| 4 | 4253 |
| 5 | 8667 |
| 6 | 21587 |
| 7 | 51841 |
| 8 | 1369453 |
| 9 | 2790747 |
| 10 | 6950947 |
| 11 | 16692641 |
| 12 | 440959613 |
| 13 | 898611867 |
| 14 | 2238183347 |
| 15 | 5374978561 |
| 16 | 141987625933 |
| 17 | 289350230427 |
| 18 | 720688086787 |
| 19 | 1730726404001 |
| 20 | 45719574590813 |
| 21 | 93169875585627 |
| 22 | 232059325762067 |
| 23 | 557288527109761 |
[13,27,67,161,4253,8667,21587,51841,1369453, 2790747,6950947,16692641,440959613,898611867, 2238183347,5374978561,141987625933,289350230427, 720688086787,1730726404001,45719574590813, 93169875585627,232059325762067,557288527109761] |