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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 13 |
| 4 | 55 |
| 5 | 183 |
| 6 | 819 |
| 7 | 2879 |
| 8 | 13133 |
| 9 | 49151 |
| 10 | 226067 |
| 11 | 872789 |
| 12 | 4051349 |
| 13 | 16053849 |
| 14 | 74860243 |
| 15 | 302223013 |
| 16 | 1415920713 |
| 17 | 5801955375 |
| 18 | 27265975349 |
| 19 | 113089016787 |
| 20 | 532974688093 |
| 21 | 2232528832155 |
| 22 | 10544821835299 |
| 23 | 44546289272039 |
| 24 | 210814127462689 |
| 25 | 896958361967791 |
| 26 | 4251815206240481 |
| 27 | 18204116761339355 |
[1,1,5,13,55,183,819,2879,13133,49151,226067, 872789,4051349,16053849,74860243,302223013, 1415920713,5801955375,27265975349,113089016787, 532974688093,2232528832155,10544821835299, 44546289272039,210814127462689,896958361967791, 4251815206240481,18204116761339355] |