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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 5 |
| 4 | 16 |
| 5 | 56 |
| 6 | 208 |
| 7 | 127 |
| 8 | 1016 |
| 9 | 4969 |
| 10 | 47223 |
| 11 | 264979 |
| 12 | 789832 |
| 13 | 7668081 |
| 14 | 4272696 |
| 15 | 130217625 |
| 16 | 883909125 |
| 17 | 9969785792 |
| 18 | 52152119144 |
| 19 | 128092980744 |
| 20 | 2166664965184 |
| 21 | 29992267884032 |
| 22 | 272465658461528 |
| 23 | 1588888484126208 |
| 24 | 10747891377020979 |
| 25 | 5480400487212279 |
| 26 | 70703132766750784 |
| 27 | 1908984584702271168 |
[1,1,5,16,56,208,127,1016,4969,47223,264979, 789832,7668081,4272696,130217625,883909125, 9969785792,52152119144,128092980744,2166664965184, 29992267884032,272465658461528,1588888484126208, 10747891377020979,5480400487212279, 70703132766750784,1908984584702271168] |