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| n | a(n) |
|---|---|
| 1 | 13 |
| 2 | 33 |
| 3 | 81 |
| 4 | 209 |
| 5 | 529 |
| 6 | 1361 |
| 7 | 3473 |
| 8 | 8913 |
| 9 | 22801 |
| 10 | 58449 |
| 11 | 149649 |
| 12 | 383441 |
| 13 | 982033 |
| 14 | 2515793 |
| 15 | 6443921 |
| 16 | 16507089 |
| 17 | 42282769 |
| 18 | 108311121 |
| 19 | 277442193 |
| 20 | 710686673 |
| 21 | 1820455441 |
| 22 | 4663202129 |
| 23 | 11945023889 |
| 24 | 30597832401 |
| 25 | 78377927953 |
| 26 | 200769257553 |
[13,33,81,209,529,1361,3473,8913,22801,58449, 149649,383441,982033,2515793,6443921,16507089, 42282769,108311121,277442193,710686673,1820455441, 4663202129,11945023889,30597832401,78377927953, 200769257553] |