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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 8 |
| 5 | 25 |
| 6 | 96 |
| 7 | 427 |
| 8 | 2176 |
| 9 | 12465 |
| 10 | 79360 |
| 11 | 555731 |
| 12 | 4245504 |
| 13 | 35135945 |
| 14 | 313155584 |
| 15 | 2990414715 |
| 16 | 30460116992 |
| 17 | 329655706465 |
| 18 | 3777576173568 |
| 19 | 45692713833379 |
| 20 | 581777702256640 |
| 21 | 7777794952988025 |
| 22 | 108932957168730112 |
| 23 | 1595024111042171723 |
| 24 | 24370173276164456448 |
[1,2,3,8,25,96,427,2176,12465,79360,555731, 4245504,35135945,313155584,2990414715,30460116992, 329655706465,3777576173568,45692713833379, 581777702256640,7777794952988025, 108932957168730112,1595024111042171723, 24370173276164456448] |