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| n | a(n) |
|---|---|
| 1 | 11 |
| 2 | 64 |
| 3 | 297 |
| 4 | 1126 |
| 5 | 3691 |
| 6 | 10928 |
| 7 | 30113 |
| 8 | 78814 |
| 9 | 198651 |
| 10 | 486784 |
| 11 | 1167337 |
| 12 | 2752166 |
| 13 | 6400283 |
| 14 | 14716576 |
| 15 | 33517185 |
| 16 | 75712510 |
| 17 | 169810507 |
| 18 | 378463376 |
| 19 | 838772201 |
| 20 | 1849580902 |
| 21 | 4059957771 |
[11,64,297,1126,3691,10928,30113,78814,198651, 486784,1167337,2752166,6400283,14716576,33517185, 75712510,169810507,378463376,838772201,1849580902, 4059957771] |