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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 8 |
| 3 | 20 |
| 4 | 50 |
| 5 | 125 |
| 6 | 314 |
| 7 | 792 |
| 8 | 2003 |
| 9 | 5079 |
| 10 | 12897 |
| 11 | 32798 |
| 12 | 83478 |
| 13 | 212657 |
| 14 | 542040 |
| 15 | 1382376 |
| 16 | 3526916 |
| 17 | 9001805 |
| 18 | 22982298 |
| 19 | 58691692 |
| 20 | 149919707 |
| 21 | 383028163 |
| 22 | 978768731 |
| 23 | 2501494110 |
| 24 | 6394118165 |
| 25 | 16346237219 |
| 26 | 41793150985 |
| 27 | 106865638630 |
[1,3,8,20,50,125,314,792,2003,5079,12897,32798, 83478,212657,542040,1382376,3526916,9001805, 22982298,58691692,149919707,383028163,978768731, 2501494110,6394118165,16346237219,41793150985, 106865638630] |