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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 28 |
| 3 | 107 |
| 4 | 380 |
| 5 | 1345 |
| 6 | 4878 |
| 7 | 18219 |
| 8 | 69736 |
| 9 | 271589 |
| 10 | 1069538 |
| 11 | 4240351 |
| 12 | 16877532 |
| 13 | 67325913 |
| 14 | 268902358 |
| 15 | 1074741203 |
| 16 | 4297097168 |
| 17 | 17184391117 |
| 18 | 68729044938 |
| 19 | 274898091975 |
| 20 | 1099554095044 |
| 21 | 4398135640001 |
| 22 | 17592372690878 |
| 23 | 70369134247867 |
| 24 | 281475790405560 |
| 25 | 1125901601341365 |
[6,28,107,380,1345,4878,18219,69736,271589, 1069538,4240351,16877532,67325913,268902358, 1074741203,4297097168,17184391117,68729044938, 274898091975,1099554095044,4398135640001, 17592372690878,70369134247867,281475790405560, 1125901601341365] |