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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 10 |
| 4 | 31 |
| 5 | 86 |
| 6 | 219 |
| 7 | 526 |
| 8 | 1215 |
| 9 | 2734 |
| 10 | 6043 |
| 11 | 13190 |
| 12 | 28527 |
| 13 | 61270 |
| 14 | 130875 |
| 15 | 278302 |
| 16 | 589567 |
| 17 | 1244894 |
| 18 | 2621115 |
| 19 | 5504662 |
| 20 | 11533935 |
| 21 | 24116806 |
| 22 | 50331163 |
| 23 | 104857070 |
| 24 | 218103231 |
| 25 | 452984206 |
| 26 | 939523419 |
| 27 | 1946156326 |
| 28 | 4026531055 |
| 29 | 8321498294 |
| 30 | 17179868283 |
| 31 | 35433479230 |
[1,1,3,10,31,86,219,526,1215,2734,6043,13190, 28527,61270,130875,278302,589567,1244894,2621115, 5504662,11533935,24116806,50331163,104857070, 218103231,452984206,939523419,1946156326, 4026531055,8321498294,17179868283,35433479230] |