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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 15 |
| 5 | 52 |
| 6 | 202 |
| 7 | 859 |
| 8 | 3930 |
| 9 | 19095 |
| 10 | 97566 |
| 11 | 520257 |
| 12 | 2877834 |
| 13 | 16434105 |
| 14 | 96505490 |
| 15 | 580864901 |
| 16 | 3573876308 |
| 17 | 22426075431 |
| 18 | 143242527870 |
| 19 | 929759705415 |
| 20 | 6123822269373 |
| 21 | 40877248201308 |
| 22 | 276229252359846 |
| 23 | 1887840181793185 |
| 24 | 13037523684646810 |
| 25 | 90913254352507057 |
[1,1,2,5,15,52,202,859,3930,19095,97566,520257, 2877834,16434105,96505490,580864901,3573876308, 22426075431,143242527870,929759705415, 6123822269373,40877248201308,276229252359846, 1887840181793185,13037523684646810, 90913254352507057] |