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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 7 |
| 2 | 35 |
| 3 | 154 |
| 4 | 636 |
| 5 | 2533 |
| 6 | 9861 |
| 7 | 37810 |
| 8 | 143451 |
| 9 | 540155 |
| 10 | 2022735 |
| 11 | 7543771 |
| 12 | 28048829 |
| 13 | 104050724 |
| 14 | 385320419 |
| 15 | 1425038684 |
| 16 | 5264963100 |
| 17 | 19437087382 |
| 18 | 71715418017 |
| 19 | 264483764116 |
| 20 | 975070823122 |
| 21 | 3593840295815 |
| 22 | 13243217176106 |
| 23 | 48793364067681 |
| 24 | 179753027448972 |
[1,7,35,154,636,2533,9861,37810,143451,540155, 2022735,7543771,28048829,104050724,385320419, 1425038684,5264963100,19437087382,71715418017, 264483764116,975070823122,3593840295815, 13243217176106,48793364067681,179753027448972] |