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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 7 |
| 4 | 14 |
| 5 | 28 |
| 6 | 66 |
| 7 | 168 |
| 8 | 378 |
| 9 | 866 |
| 10 | 2128 |
| 11 | 5065 |
| 12 | 12000 |
| 13 | 28866 |
| 14 | 69652 |
| 15 | 167994 |
| 16 | 405058 |
| 17 | 981305 |
| 18 | 2381232 |
| 19 | 5776411 |
| 20 | 14040684 |
| 21 | 34175851 |
| 22 | 83246764 |
| 23 | 202960219 |
| 24 | 495273680 |
| 25 | 1209625253 |
| 26 | 2956269734 |
| 27 | 7229756488 |
| 28 | 17692733704 |
| 29 | 43322486571 |
| 30 | 106136686984 |
[1,2,7,14,28,66,168,378,866,2128,5065,12000,28866, 69652,167994,405058,981305,2381232,5776411, 14040684,34175851,83246764,202960219,495273680, 1209625253,2956269734,7229756488,17692733704, 43322486571,106136686984] |