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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 6 |
| 3 | 9 |
| 4 | 25 |
| 5 | 58 |
| 6 | 152 |
| 7 | 368 |
| 8 | 904 |
| 9 | 2211 |
| 10 | 5420 |
| 11 | 13257 |
| 12 | 32485 |
| 13 | 79687 |
| 14 | 195459 |
| 15 | 479166 |
| 16 | 1174486 |
| 17 | 2879048 |
| 18 | 7057869 |
| 19 | 17302114 |
| 20 | 42416167 |
| 21 | 103983959 |
| 22 | 254916060 |
| 23 | 624918591 |
| 24 | 1531968302 |
| 25 | 3755586548 |
| 26 | 9206752113 |
| 27 | 22570177681 |
| 28 | 55330344496 |
| 29 | 135641228111 |
[3,6,9,25,58,152,368,904,2211,5420,13257,32485, 79687,195459,479166,1174486,2879048,7057869, 17302114,42416167,103983959,254916060,624918591, 1531968302,3755586548,9206752113,22570177681, 55330344496,135641228111] |