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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 12 |
| 5 | 33 |
| 6 | 99 |
| 7 | 286 |
| 8 | 794 |
| 9 | 2235 |
| 10 | 6193 |
| 11 | 17584 |
| 12 | 49978 |
| 13 | 141115 |
| 14 | 397871 |
| 15 | 1119496 |
| 16 | 3143540 |
| 17 | 8816661 |
| 18 | 24794657 |
| 19 | 69734595 |
| 20 | 196208514 |
| 21 | 550646282 |
| 22 | 1545975038 |
| 23 | 4342120668 |
| 24 | 12196239620 |
| 25 | 34268355937 |
| 26 | 96256484372 |
| 27 | 270382410201 |
[1,2,5,12,33,99,286,794,2235,6193,17584,49978, 141115,397871,1119496,3143540,8816661,24794657, 69734595,196208514,550646282,1545975038, 4342120668,12196239620,34268355937,96256484372, 270382410201] |