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| n | a(n) |
|---|---|
| 1 | 5 |
| 2 | 18 |
| 3 | 59 |
| 4 | 184 |
| 5 | 561 |
| 6 | 1694 |
| 7 | 5095 |
| 8 | 15300 |
| 9 | 45917 |
| 10 | 137770 |
| 11 | 413331 |
| 12 | 1240016 |
| 13 | 3720073 |
| 14 | 11160246 |
| 15 | 33480767 |
| 16 | 100442332 |
| 17 | 301327029 |
| 18 | 903981122 |
| 19 | 2711943403 |
| 20 | 8135830248 |
| 21 | 24407490785 |
| 22 | 73222472398 |
| 23 | 219667417239 |
| 24 | 659002251764 |
| 25 | 1977006755341 |
[5,18,59,184,561,1694,5095,15300,45917,137770, 413331,1240016,3720073,11160246,33480767, 100442332,301327029,903981122,2711943403, 8135830248,24407490785,73222472398,219667417239, 659002251764,1977006755341] |