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| n | a(n) |
|---|---|
| 1 | 26 |
| 2 | 64 |
| 3 | 140 |
| 4 | 290 |
| 5 | 586 |
| 6 | 1172 |
| 7 | 2336 |
| 8 | 4654 |
| 9 | 9278 |
| 10 | 18512 |
| 11 | 36964 |
| 12 | 73850 |
| 13 | 147602 |
| 14 | 295084 |
| 15 | 590024 |
| 16 | 1179878 |
| 17 | 2359558 |
| 18 | 4718888 |
| 19 | 9437516 |
| 20 | 18874738 |
| 21 | 37749146 |
| 22 | 75497924 |
| 23 | 150995440 |
| 24 | 301990430 |
| 25 | 603980366 |
| 26 | 1207960192 |
| 27 | 2415919796 |
| 28 | 4831838954 |
[26,64,140,290,586,1172,2336,4654,9278,18512, 36964,73850,147602,295084,590024,1179878,2359558, 4718888,9437516,18874738,37749146,75497924, 150995440,301990430,603980366,1207960192, 2415919796,4831838954] |