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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 17 |
| 4 | 57 |
| 5 | 207 |
| 6 | 770 |
| 7 | 2956 |
| 8 | 11511 |
| 9 | 45389 |
| 10 | 181551 |
| 11 | 732140 |
| 12 | 2975463 |
| 13 | 12172039 |
| 14 | 50107475 |
| 15 | 207221750 |
| 16 | 860713442 |
| 17 | 3589342898 |
| 18 | 15020205470 |
| 19 | 63043294686 |
| 20 | 265353326080 |
| 21 | 1119765415144 |
| 22 | 4736096978950 |
| 23 | 20073601677112 |
| 24 | 85247397615355 |
| 25 | 362674562863687 |
| 26 | 1545498849494243 |
| 27 | 6596146668760089 |
[1,2,5,17,57,207,770,2956,11511,45389,181551, 732140,2975463,12172039,50107475,207221750, 860713442,3589342898,15020205470,63043294686, 265353326080,1119765415144,4736096978950, 20073601677112,85247397615355,362674562863687, 1545498849494243,6596146668760089] |