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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 10 |
| 5 | 27 |
| 6 | 66 |
| 7 | 181 |
| 8 | 470 |
| 9 | 1263 |
| 10 | 3310 |
| 11 | 8767 |
| 12 | 22980 |
| 13 | 60449 |
| 14 | 158354 |
| 15 | 415353 |
| 16 | 1087690 |
| 17 | 2849675 |
| 18 | 7461318 |
| 19 | 19539429 |
| 20 | 51156950 |
| 21 | 133944931 |
| 22 | 350677822 |
| 23 | 918123935 |
| 24 | 2403693960 |
| 25 | 6293050657 |
| 26 | 16475457986 |
| 27 | 43133566061 |
[1,2,5,10,27,66,181,470,1263,3310,8767,22980, 60449,158354,415353,1087690,2849675,7461318, 19539429,51156950,133944931,350677822,918123935, 2403693960,6293050657,16475457986,43133566061] |