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| n | a(n) |
|---|---|
| 9 | 1 |
| 10 | 8 |
| 11 | 52 |
| 12 | 270 |
| 13 | 1203 |
| 14 | 4682 |
| 15 | 16346 |
| 16 | 51901 |
| 17 | 151945 |
| 18 | 414116 |
| 19 | 1059945 |
| 20 | 2565394 |
| 21 | 5907070 |
| 22 | 13005279 |
| 23 | 27498902 |
| 24 | 56052155 |
| 25 | 110506991 |
| 26 | 211327231 |
| 27 | 393002091 |
| 28 | 712326630 |
| 29 | 1260881177 |
| 30 | 2183476067 |
| 31 | 3705027759 |
| 32 | 6169083918 |
| 33 | 10092371963 |
[1,8,52,270,1203,4682,16346,51901,151945,414116, 1059945,2565394,5907070,13005279,27498902, 56052155,110506991,211327231,393002091,712326630, 1260881177,2183476067,3705027759,6169083918, 10092371963] |