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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 9 |
| 3 | 25 |
| 4 | 71 |
| 5 | 203 |
| 6 | 585 |
| 7 | 1689 |
| 8 | 4881 |
| 9 | 14113 |
| 10 | 40839 |
| 11 | 118287 |
| 12 | 342951 |
| 13 | 995303 |
| 14 | 2891309 |
| 15 | 8406925 |
| 16 | 24466555 |
| 17 | 71267575 |
| 18 | 207771209 |
| 19 | 606238465 |
| 20 | 1770339721 |
| 21 | 5173862121 |
| 22 | 15132414675 |
| 23 | 44292151875 |
| 24 | 129736008621 |
| 25 | 380276585553 |
| 26 | 1115408929215 |
| 27 | 3273817075159 |
| 28 | 9615035204811 |
| 29 | 28256221883283 |
| 30 | 83087327433025 |
[1,3,9,25,71,203,585,1689,4881,14113,40839,118287, 342951,995303,2891309,8406925,24466555,71267575, 207771209,606238465,1770339721,5173862121, 15132414675,44292151875,129736008621,380276585553, 1115408929215,3273817075159,9615035204811, 28256221883283,83087327433025] |