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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 12 |
| 3 | 104 |
| 4 | 1104 |
| 5 | 13472 |
| 6 | 183488 |
| 7 | 2749056 |
| 8 | 44996864 |
| 9 | 802443776 |
| 10 | 15579089920 |
| 11 | 329170937856 |
| 12 | 7562372632576 |
| 13 | 188526816632832 |
| 14 | 5083702487990272 |
| 15 | 147676990509580288 |
| 16 | 4600624321049722880 |
| 17 | 153012055369679241216 |
| 18 | 5409813656756850262016 |
| 19 | 202534832564335070937088 |
| 20 | 8001606648308588124045312 |
[1,2,12,104,1104,13472,183488,2749056,44996864, 802443776,15579089920,329170937856,7562372632576, 188526816632832,5083702487990272, 147676990509580288,4600624321049722880, 153012055369679241216,5409813656756850262016, 202534832564335070937088, 8001606648308588124045312] |