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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 44 |
| 2 | 198 |
| 3 | 758 |
| 4 | 2824 |
| 5 | 10530 |
| 6 | 39516 |
| 7 | 149274 |
| 8 | 567120 |
| 9 | 2164898 |
| 10 | 8297206 |
| 11 | 31907214 |
| 12 | 123053938 |
| 13 | 475753142 |
| 14 | 1843357752 |
| 15 | 7155936162 |
| 16 | 27826486272 |
| 17 | 108369397602 |
| 18 | 422614721742 |
| 19 | 1650118887102 |
| 20 | 6450143419962 |
| 21 | 25238550057222 |
[1,44,198,758,2824,10530,39516,149274,567120, 2164898,8297206,31907214,123053938,475753142, 1843357752,7155936162,27826486272,108369397602, 422614721742,1650118887102,6450143419962, 25238550057222] |