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| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 21 |
| 3 | 70 |
| 4 | 245 |
| 5 | 882 |
| 6 | 3234 |
| 7 | 12005 |
| 8 | 44933 |
| 9 | 169099 |
| 10 | 638666 |
| 11 | 2417807 |
| 12 | 9167018 |
| 13 | 34790490 |
| 14 | 132119827 |
| 15 | 501941055 |
| 16 | 1907443237 |
| 17 | 7249766678 |
| 18 | 27557748813 |
| 19 | 104759610858 |
| 20 | 398257159370 |
| 21 | 1514069805269 |
| 22 | 5756205681709 |
| 23 | 21884262613787 |
| 24 | 83201447389466 |
| 25 | 316323894905207 |
[7,21,70,245,882,3234,12005,44933,169099,638666, 2417807,9167018,34790490,132119827,501941055, 1907443237,7249766678,27557748813,104759610858, 398257159370,1514069805269,5756205681709, 21884262613787,83201447389466,316323894905207] |