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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 44 |
| 4 | 302 |
| 5 | 2437 |
| 6 | 22143 |
| 7 | 220663 |
| 8 | 2377322 |
| 9 | 27462836 |
| 10 | 338270681 |
| 11 | 4422338285 |
| 12 | 61114545578 |
| 13 | 889542935517 |
| 14 | 13593252066134 |
| 15 | 217461100417945 |
| 16 | 3632859088845390 |
| 17 | 63233532604594586 |
| 18 | 1144455373221119025 |
[1,2,8,44,302,2437,22143,220663,2377322,27462836, 338270681,4422338285,61114545578,889542935517, 13593252066134,217461100417945,3632859088845390, 63233532604594586,1144455373221119025] |