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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 4 |
| 4 | 13 |
| 5 | 13 |
| 6 | 40 |
| 7 | 40 |
| 8 | 121 |
| 9 | 121 |
| 10 | 364 |
| 11 | 364 |
| 12 | 1093 |
| 13 | 1093 |
| 14 | 3280 |
| 15 | 3280 |
| 16 | 9841 |
| 17 | 9841 |
| 18 | 29524 |
| 19 | 29524 |
| 20 | 88573 |
| 21 | 88573 |
| 22 | 265720 |
| 23 | 265720 |
| 24 | 797161 |
| 25 | 797161 |
| 26 | 2391484 |
| 27 | 2391484 |
| 28 | 7174453 |
| 29 | 7174453 |
| 30 | 21523360 |
| 31 | 21523360 |
| 32 | 64570081 |
| 33 | 64570081 |
| 34 | 193710244 |
[1,1,4,4,13,13,40,40,121,121,364,364,1093,1093, 3280,3280,9841,9841,29524,29524,88573,88573, 265720,265720,797161,797161,2391484,2391484, 7174453,7174453,21523360,21523360,64570081, 64570081,193710244] |