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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 12 |
| 4 | 39 |
| 5 | 131 |
| 6 | 426 |
| 7 | 1389 |
| 8 | 4503 |
| 9 | 14596 |
| 10 | 47259 |
| 11 | 152991 |
| 12 | 495162 |
| 13 | 1602521 |
| 14 | 5186067 |
| 15 | 16782828 |
| 16 | 54310911 |
| 17 | 175754731 |
| 18 | 568755690 |
| 19 | 1840534485 |
| 20 | 5956098495 |
| 21 | 19274345876 |
| 22 | 62373103443 |
| 23 | 201843619047 |
| 24 | 653179698234 |
| 25 | 2113733947681 |
| 26 | 6840186809691 |
| 27 | 22135309606524 |
| 28 | 71631366769623 |
[1,3,12,39,131,426,1389,4503,14596,47259,152991, 495162,1602521,5186067,16782828,54310911, 175754731,568755690,1840534485,5956098495, 19274345876,62373103443,201843619047,653179698234, 2113733947681,6840186809691,22135309606524, 71631366769623] |