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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 56 |
| 6 | 202 |
| 7 | 715 |
| 8 | 3244 |
| 9 | 12945 |
| 10 | 49742 |
| 11 | 238048 |
| 12 | 996158 |
| 13 | 3991995 |
| 14 | 19676358 |
| 15 | 84649176 |
| 16 | 347993910 |
| 17 | 1747681160 |
| 18 | 7656026268 |
| 19 | 32018897274 |
| 20 | 162900330572 |
| 21 | 722787262419 |
| 22 | 3060338457400 |
| 23 | 15718332812096 |
| 24 | 70407433197686 |
[1,2,5,14,56,202,715,3244,12945,49742,238048, 996158,3991995,19676358,84649176,347993910, 1747681160,7656026268,32018897274,162900330572, 722787262419,3060338457400,15718332812096, 70407433197686] |