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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 11 |
| 4 | 21 |
| 5 | 31 |
| 6 | 113 |
| 7 | 363 |
| 8 | 813 |
| 9 | 1751 |
| 10 | 5001 |
| 11 | 14051 |
| 12 | 34053 |
| 13 | 82063 |
| 14 | 218273 |
| 15 | 579291 |
| 16 | 1452381 |
| 17 | 3638471 |
| 18 | 9447993 |
| 19 | 24526163 |
| 20 | 62318133 |
| 21 | 158325631 |
| 22 | 407598161 |
| 23 | 1049289291 |
| 24 | 2679681933 |
| 25 | 6843284663 |
| 26 | 17562012393 |
| 27 | 45069368771 |
| 28 | 115317418341 |
[2,3,11,21,31,113,363,813,1751,5001,14051,34053, 82063,218273,579291,1452381,3638471,9447993, 24526163,62318133,158325631,407598161,1049289291, 2679681933,6843284663,17562012393,45069368771, 115317418341] |