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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 17 |
| 5 | 59 |
| 6 | 209 |
| 7 | 783 |
| 8 | 2969 |
| 9 | 11818 |
| 10 | 48041 |
| 11 | 197875 |
| 12 | 829325 |
| 13 | 3504606 |
| 14 | 15030624 |
| 15 | 65140862 |
| 16 | 284465160 |
| 17 | 1252897588 |
| 18 | 5548473208 |
| 19 | 24743623447 |
| 20 | 110991861676 |
| 21 | 500241513919 |
| 22 | 2265903803712 |
| 23 | 10302193469158 |
| 24 | 47033998962322 |
| 25 | 215522897042267 |
| 26 | 990747858248266 |
| 27 | 4569280467583454 |
| 28 | 21129681319052978 |
[1,1,2,5,17,59,209,783,2969,11818,48041,197875, 829325,3504606,15030624,65140862,284465160, 1252897588,5548473208,24743623447,110991861676, 500241513919,2265903803712,10302193469158, 47033998962322,215522897042267,990747858248266, 4569280467583454,21129681319052978] |