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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 16 |
| 5 | 50 |
| 6 | 155 |
| 7 | 520 |
| 8 | 1852 |
| 9 | 6689 |
| 10 | 24152 |
| 11 | 88895 |
| 12 | 336276 |
| 13 | 1290375 |
| 14 | 4970796 |
| 15 | 19272883 |
| 16 | 75691051 |
| 17 | 300545743 |
| 18 | 1199594439 |
| 19 | 4804949939 |
| 20 | 19368329062 |
| 21 | 78661855921 |
| 22 | 321113507062 |
| 23 | 1314680128753 |
| 24 | 5401412322285 |
| 25 | 22300830778267 |
| 26 | 92477666047975 |
| 27 | 384557465300678 |
| 28 | 1602917291647183 |
| 29 | 6702572454835313 |
[1,1,2,5,16,50,155,520,1852,6689,24152,88895, 336276,1290375,4970796,19272883,75691051, 300545743,1199594439,4804949939,19368329062, 78661855921,321113507062,1314680128753, 5401412322285,22300830778267,92477666047975, 384557465300678,1602917291647183,6702572454835313] |