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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 11 |
| 4 | 23 |
| 5 | 50 |
| 6 | 110 |
| 7 | 242 |
| 8 | 529 |
| 9 | 1158 |
| 10 | 2537 |
| 11 | 5556 |
| 12 | 12167 |
| 13 | 26645 |
| 14 | 58351 |
| 15 | 127785 |
| 16 | 279841 |
| 17 | 612835 |
| 18 | 1342070 |
| 19 | 2939052 |
| 20 | 6436343 |
| 21 | 14095197 |
| 22 | 30867617 |
| 23 | 67598188 |
| 24 | 148035889 |
| 25 | 324189523 |
| 26 | 709955183 |
| 27 | 1554758333 |
[1,2,5,11,23,50,110,242,529,1158,2537,5556,12167, 26645,58351,127785,279841,612835,1342070,2939052, 6436343,14095197,30867617,67598188,148035889, 324189523,709955183,1554758333] |