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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 13 |
| 4 | 33 |
| 5 | 85 |
| 6 | 218 |
| 7 | 559 |
| 8 | 1435 |
| 9 | 3682 |
| 10 | 9448 |
| 11 | 24244 |
| 12 | 62210 |
| 13 | 159633 |
| 14 | 409622 |
| 15 | 1051099 |
| 16 | 2697145 |
| 17 | 6920936 |
| 18 | 17759282 |
| 19 | 45570729 |
| 20 | 116935544 |
| 21 | 300059313 |
| 22 | 769959141 |
| 23 | 1975732973 |
| 24 | 5069776531 |
| 25 | 13009163899 |
| 26 | 33381815615 |
| 27 | 85658511370 |
| 28 | 219801722429 |
| 29 | 564016306267 |
[1,2,5,13,33,85,218,559,1435,3682,9448,24244, 62210,159633,409622,1051099,2697145,6920936, 17759282,45570729,116935544,300059313,769959141, 1975732973,5069776531,13009163899,33381815615, 85658511370,219801722429,564016306267] |