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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 1 |
| 4 | 4 |
| 5 | 5 |
| 6 | 14 |
| 7 | 21 |
| 8 | 51 |
| 9 | 102 |
| 10 | 249 |
| 11 | 555 |
| 12 | 1358 |
| 13 | 3201 |
| 14 | 7890 |
| 15 | 19232 |
| 16 | 47869 |
| 17 | 118955 |
| 18 | 298875 |
| 19 | 752039 |
| 20 | 1904621 |
| 21 | 4835666 |
| 22 | 12330144 |
| 23 | 31521037 |
| 24 | 80836979 |
| 25 | 207803455 |
| 26 | 535535393 |
| 27 | 1383064966 |
| 28 | 3579351724 |
| 29 | 9280561947 |
[1,2,1,4,5,14,21,51,102,249,555,1358,3201,7890, 19232,47869,118955,298875,752039,1904621,4835666, 12330144,31521037,80836979,207803455,535535393, 1383064966,3579351724,9280561947] |