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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 3 |
| 7 | 8 |
| 8 | 25 |
| 9 | 83 |
| 10 | 257 |
| 11 | 788 |
| 12 | 2491 |
| 13 | 7885 |
| 14 | 25099 |
| 15 | 80481 |
| 16 | 264505 |
| 17 | 884517 |
| 18 | 2994535 |
| 19 | 10208806 |
| 20 | 35095825 |
| 21 | 121699761 |
| 22 | 424273761 |
| 23 | 1487693075 |
| 24 | 5244197347 |
| 25 | 18584820912 |
| 26 | 66169376686 |
| 27 | 236592018517 |
| 28 | 849466213882 |
| 29 | 3061492852986 |
| 30 | 11072927827447 |
[1,1,1,1,1,3,8,25,83,257,788,2491,7885,25099, 80481,264505,884517,2994535,10208806,35095825, 121699761,424273761,1487693075,5244197347, 18584820912,66169376686,236592018517,849466213882, 3061492852986,11072927827447] |