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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 3 |
| 6 | 8 |
| 7 | 15 |
| 8 | 42 |
| 9 | 94 |
| 10 | 246 |
| 11 | 613 |
| 12 | 1645 |
| 13 | 4361 |
| 14 | 11980 |
| 15 | 33023 |
| 16 | 92484 |
| 17 | 259762 |
| 18 | 735310 |
| 19 | 2088403 |
| 20 | 5961138 |
| 21 | 17070131 |
| 22 | 49059542 |
| 23 | 141402328 |
| 24 | 408736264 |
| 25 | 1184435227 |
| 26 | 3440434897 |
| 27 | 10014880408 |
| 28 | 29211476668 |
| 29 | 85362417183 |
| 30 | 249882401380 |
| 31 | 732670159161 |
| 32 | 2151506490430 |
[1,1,1,3,3,8,15,42,94,246,613,1645,4361,11980, 33023,92484,259762,735310,2088403,5961138, 17070131,49059542,141402328,408736264,1184435227, 3440434897,10014880408,29211476668,85362417183, 249882401380,732670159161,2151506490430] |