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| n | a(n) |
|---|---|
| 3 | 0 |
| 4 | 1 |
| 5 | 1 |
| 6 | 3 |
| 7 | 9 |
| 8 | 23 |
| 9 | 60 |
| 10 | 164 |
| 11 | 443 |
| 12 | 1209 |
| 13 | 3319 |
| 14 | 9150 |
| 15 | 25326 |
| 16 | 70335 |
| 17 | 195870 |
| 18 | 546823 |
| 19 | 1529935 |
| 20 | 4288662 |
| 21 | 12042447 |
| 22 | 33866604 |
| 23 | 95373852 |
| 24 | 268925258 |
| 25 | 759157224 |
| 26 | 2145298117 |
| 27 | 6068251826 |
| 28 | 17180172176 |
| 29 | 48680092670 |
| 30 | 138041661905 |
| 31 | 391725281701 |
| 32 | 1112360700816 |
| 33 | 3160707529077 |
[0,1,1,3,9,23,60,164,443,1209,3319,9150,25326, 70335,195870,546823,1529935,4288662,12042447, 33866604,95373852,268925258,759157224,2145298117, 6068251826,17180172176,48680092670,138041661905, 391725281701,1112360700816,3160707529077] |