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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 24 |
| 5 | 76 |
| 6 | 251 |
| 7 | 838 |
| 8 | 2926 |
| 9 | 10169 |
| 10 | 36400 |
| 11 | 130395 |
| 12 | 474831 |
| 13 | 1733605 |
| 14 | 6403971 |
| 15 | 23684098 |
| 16 | 88447620 |
| 17 | 330426207 |
| 18 | 1243990000 |
| 19 | 4685124726 |
| 20 | 17751802480 |
| 21 | 67287467042 |
| 22 | 256301925243 |
| 23 | 976546214354 |
| 24 | 3736114526010 |
| 25 | 14296501505222 |
| 26 | 54897699531735 |
| 27 | 210834772852983 |
| 28 | 812124034397346 |
| 29 | 3128637177989858 |
[1,1,3,8,24,76,251,838,2926,10169,36400,130395, 474831,1733605,6403971,23684098,88447620, 330426207,1243990000,4685124726,17751802480, 67287467042,256301925243,976546214354, 3736114526010,14296501505222,54897699531735, 210834772852983,812124034397346,3128637177989858] |