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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 10 |
| 3 | 35 |
| 4 | 124 |
| 5 | 441 |
| 6 | 1570 |
| 7 | 5591 |
| 8 | 19912 |
| 9 | 70917 |
| 10 | 252574 |
| 11 | 899555 |
| 12 | 3203812 |
| 13 | 11410545 |
| 14 | 40639258 |
| 15 | 144738863 |
| 16 | 515495104 |
| 17 | 1835963037 |
| 18 | 6538879318 |
| 19 | 23288564027 |
| 20 | 82943450716 |
| 21 | 295407480201 |
| 22 | 1052109342034 |
| 23 | 3747142986503 |
| 24 | 13345647643576 |
| 25 | 47531228903733 |
| 26 | 169284981998350 |
[1,3,10,35,124,441,1570,5591,19912,70917,252574, 899555,3203812,11410545,40639258,144738863, 515495104,1835963037,6538879318,23288564027, 82943450716,295407480201,1052109342034, 3747142986503,13345647643576,47531228903733, 169284981998350] |