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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 8 |
| 4 | 16 |
| 5 | 32 |
| 6 | 189 |
| 7 | 1832 |
| 8 | 11976 |
| 9 | 56900 |
| 10 | 218700 |
| 11 | 727124 |
| 12 | 2726981 |
| 13 | 12253538 |
| 14 | 62679368 |
| 15 | 325994136 |
| 16 | 1595601732 |
| 17 | 7138298060 |
| 18 | 30826222249 |
| 19 | 133888313984 |
| 20 | 599193793748 |
| 21 | 2771350054416 |
| 22 | 13034384509528 |
| 23 | 60837363967864 |
| 24 | 279515497785209 |
| 25 | 1268615827196786 |
| 26 | 5735159834461216 |
[1,2,4,8,16,32,189,1832,11976,56900,218700,727124, 2726981,12253538,62679368,325994136,1595601732, 7138298060,30826222249,133888313984,599193793748, 2771350054416,13034384509528,60837363967864, 279515497785209,1268615827196786,5735159834461216] |