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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 9 |
| 3 | 14 |
| 4 | 23 |
| 5 | 43 |
| 6 | 78 |
| 7 | 139 |
| 8 | 249 |
| 9 | 450 |
| 10 | 815 |
| 11 | 1475 |
| 12 | 2674 |
| 13 | 4859 |
| 14 | 8841 |
| 15 | 16102 |
| 16 | 29359 |
| 17 | 53587 |
| 18 | 97894 |
| 19 | 178971 |
| 20 | 327425 |
| 21 | 599394 |
| 22 | 1097871 |
| 23 | 2011875 |
| 24 | 3688402 |
| 25 | 6764595 |
| 26 | 12410585 |
| 27 | 22775742 |
| 28 | 41808791 |
| 29 | 76765147 |
| 30 | 140977582 |
| 31 | 258949451 |
| 32 | 475718009 |
| 33 | 874068802 |
[3,9,14,23,43,78,139,249,450,815,1475,2674,4859, 8841,16102,29359,53587,97894,178971,327425,599394, 1097871,2011875,3688402,6764595,12410585,22775742, 41808791,76765147,140977582,258949451,475718009, 874068802] |