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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 28 |
| 5 | 91 |
| 6 | 339 |
| 7 | 1219 |
| 8 | 4729 |
| 9 | 17967 |
| 10 | 72051 |
| 11 | 284889 |
| 12 | 1168359 |
| 13 | 4742941 |
| 14 | 19784801 |
| 15 | 81931257 |
| 16 | 346432579 |
| 17 | 1457019579 |
| 18 | 6229024211 |
| 19 | 26524446504 |
| 20 | 114437092724 |
| 21 | 492263548721 |
| 22 | 2140219854313 |
| 23 | 9284528309060 |
| 24 | 40632801423118 |
| 25 | 177536118818556 |
| 26 | 781408211355630 |
| 27 | 3435232456516649 |
| 28 | 15195467329981059 |
[1,1,3,8,28,91,339,1219,4729,17967,72051,284889, 1168359,4742941,19784801,81931257,346432579, 1457019579,6229024211,26524446504,114437092724, 492263548721,2140219854313,9284528309060, 40632801423118,177536118818556,781408211355630, 3435232456516649,15195467329981059] |