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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 11 |
| 3 | 16 |
| 4 | 65 |
| 5 | 178 |
| 6 | 619 |
| 7 | 2784 |
| 8 | 4929 |
| 9 | 24482 |
| 10 | 47371 |
| 11 | 133872 |
| 12 | 659713 |
| 13 | 1196754 |
| 14 | 5945771 |
| 15 | 8408000 |
| 16 | 34643073 |
| 17 | 94509378 |
| 18 | 313886731 |
| 19 | 1475558352 |
| 20 | 2552700993 |
| 21 | 12739900146 |
| 22 | 24581737195 |
| 23 | 70102639264 |
| 24 | 350315469377 |
| 25 | 639249412322 |
| 26 | 3139708751627 |
| 27 | 4623469310128 |
| 28 | 18666316402561 |
[1,2,11,16,65,178,619,2784,4929,24482,47371, 133872,659713,1196754,5945771,8408000,34643073, 94509378,313886731,1475558352,2552700993, 12739900146,24581737195,70102639264,350315469377, 639249412322,3139708751627,4623469310128, 18666316402561] |