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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 29 |
| 5 | 96 |
| 6 | 350 |
| 7 | 1292 |
| 8 | 4899 |
| 9 | 18831 |
| 10 | 74312 |
| 11 | 296745 |
| 12 | 1198823 |
| 13 | 4886726 |
| 14 | 20140263 |
| 15 | 83681564 |
| 16 | 350091692 |
| 17 | 1473326213 |
| 18 | 6238321647 |
| 19 | 26559287386 |
| 20 | 113604606928 |
| 21 | 487942278945 |
| 22 | 2104187218979 |
| 23 | 9108794276136 |
| 24 | 39565656120954 |
| 25 | 172386792190214 |
| 26 | 753267792657033 |
| 27 | 3300723149321924 |
| 28 | 14500845883582327 |
[1,1,3,9,29,96,350,1292,4899,18831,74312,296745, 1198823,4886726,20140263,83681564,350091692, 1473326213,6238321647,26559287386,113604606928, 487942278945,2104187218979,9108794276136, 39565656120954,172386792190214,753267792657033, 3300723149321924,14500845883582327] |