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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 8 |
| 3 | 33 |
| 4 | 135 |
| 5 | 542 |
| 6 | 2168 |
| 7 | 8673 |
| 8 | 34695 |
| 9 | 138782 |
| 10 | 555128 |
| 11 | 2220513 |
| 12 | 8882055 |
| 13 | 35528222 |
| 14 | 142112888 |
| 15 | 568451553 |
| 16 | 2273806215 |
| 17 | 9095224862 |
| 18 | 36380899448 |
| 19 | 145523597793 |
| 20 | 582094391175 |
| 21 | 2328377564702 |
| 22 | 9313510258808 |
| 23 | 37254041035233 |
[2,8,33,135,542,2168,8673,34695,138782,555128, 2220513,8882055,35528222,142112888,568451553, 2273806215,9095224862,36380899448,145523597793, 582094391175,2328377564702,9313510258808, 37254041035233] |