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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 6 |
| 3 | 9 |
| 4 | 26 |
| 5 | 61 |
| 6 | 154 |
| 7 | 374 |
| 8 | 941 |
| 9 | 2357 |
| 10 | 5963 |
| 11 | 15074 |
| 12 | 38168 |
| 13 | 96641 |
| 14 | 244836 |
| 15 | 620311 |
| 16 | 1571854 |
| 17 | 3983147 |
| 18 | 10093850 |
| 19 | 25579490 |
| 20 | 64823479 |
| 21 | 164276135 |
| 22 | 416311227 |
| 23 | 1055023990 |
| 24 | 2673664936 |
| 25 | 6775663297 |
| 26 | 17171047596 |
| 27 | 43515284891 |
| 28 | 110277499816 |
[3,6,9,26,61,154,374,941,2357,5963,15074,38168, 96641,244836,620311,1571854,3983147,10093850, 25579490,64823479,164276135,416311227,1055023990, 2673664936,6775663297,17171047596,43515284891, 110277499816] |