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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 21 |
| 3 | 77 |
| 4 | 277 |
| 5 | 1005 |
| 6 | 3669 |
| 7 | 13421 |
| 8 | 49109 |
| 9 | 179693 |
| 10 | 657493 |
| 11 | 2405741 |
| 12 | 8802517 |
| 13 | 32208109 |
| 14 | 117848405 |
| 15 | 431203437 |
| 16 | 1577759189 |
| 17 | 5772968941 |
| 18 | 21123103317 |
| 19 | 77288739693 |
| 20 | 282796954325 |
| 21 | 1034744746733 |
| 22 | 3786096966485 |
| 23 | 13853204169325 |
| 24 | 50688418034645 |
| 25 | 185467253023213 |
| 26 | 678618573585493 |
| 27 | 2483043021926765 |
[1,5,21,77,277,1005,3669,13421,49109,179693, 657493,2405741,8802517,32208109,117848405, 431203437,1577759189,5772968941,21123103317, 77288739693,282796954325,1034744746733, 3786096966485,13853204169325,50688418034645, 185467253023213,678618573585493,2483043021926765] |