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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 12 |
| 3 | 42 |
| 4 | 187 |
| 5 | 620 |
| 6 | 1961 |
| 7 | 5799 |
| 8 | 16464 |
| 9 | 45093 |
| 10 | 118742 |
| 11 | 300691 |
| 12 | 732741 |
| 13 | 1722676 |
| 14 | 3918437 |
| 15 | 8645952 |
| 16 | 18545343 |
| 17 | 38739703 |
| 18 | 78930954 |
| 19 | 157075640 |
| 20 | 305697694 |
| 21 | 582518911 |
| 22 | 1088033189 |
| 23 | 1994062088 |
| 24 | 3589405583 |
| 25 | 6351714734 |
| 26 | 11059029166 |
[6,12,42,187,620,1961,5799,16464,45093,118742, 300691,732741,1722676,3918437,8645952,18545343, 38739703,78930954,157075640,305697694,582518911, 1088033189,1994062088,3589405583,6351714734, 11059029166] |