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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 42 |
| 6 | 132 |
| 7 | 428 |
| 8 | 1415 |
| 9 | 4730 |
| 10 | 15901 |
| 11 | 53593 |
| 12 | 180809 |
| 13 | 610157 |
| 14 | 2058962 |
| 15 | 6947145 |
| 16 | 23437854 |
| 17 | 79067006 |
| 18 | 266717300 |
| 19 | 899693960 |
| 20 | 3034814143 |
| 21 | 10236853534 |
| 22 | 34530252629 |
| 23 | 116475001757 |
| 24 | 392885252033 |
[1,2,5,14,42,132,428,1415,4730,15901,53593,180809, 610157,2058962,6947145,23437854,79067006, 266717300,899693960,3034814143,10236853534, 34530252629,116475001757,392885252033] |