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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 11 |
| 4 | 28 |
| 5 | 70 |
| 6 | 184 |
| 7 | 486 |
| 8 | 1313 |
| 9 | 3576 |
| 10 | 9851 |
| 11 | 27319 |
| 12 | 76286 |
| 13 | 214120 |
| 14 | 603858 |
| 15 | 1709719 |
| 16 | 4857959 |
| 17 | 13845948 |
| 18 | 39572583 |
| 19 | 113380652 |
| 20 | 325576692 |
| 21 | 936796592 |
| 22 | 2700456452 |
| 23 | 7797587816 |
| 24 | 22550434989 |
| 25 | 65308288346 |
| 26 | 189388557677 |
[1,2,5,11,28,70,184,486,1313,3576,9851,27319, 76286,214120,603858,1709719,4857959,13845948, 39572583,113380652,325576692,936796592,2700456452, 7797587816,22550434989,65308288346,189388557677] |