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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 7 |
| 2 | 27 |
| 3 | 113 |
| 4 | 447 |
| 5 | 1743 |
| 6 | 6789 |
| 7 | 26371 |
| 8 | 102399 |
| 9 | 397425 |
| 10 | 1542327 |
| 11 | 5984815 |
| 12 | 23222957 |
| 13 | 90110355 |
| 14 | 349647247 |
| 15 | 1356699401 |
| 16 | 5264252887 |
| 17 | 20426289087 |
| 18 | 79257818197 |
| 19 | 307535089027 |
| 20 | 1193293339871 |
| 21 | 4630199918049 |
| 22 | 17966035966423 |
| 23 | 69711557106543 |
[1,7,27,113,447,1743,6789,26371,102399,397425, 1542327,5984815,23222957,90110355,349647247, 1356699401,5264252887,20426289087,79257818197, 307535089027,1193293339871,4630199918049, 17966035966423,69711557106543] |