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| n | a(n) |
|---|---|
| 1 | 102 |
| 2 | 390 |
| 3 | 1517 |
| 4 | 5805 |
| 5 | 22346 |
| 6 | 86251 |
| 7 | 332419 |
| 8 | 1281181 |
| 9 | 4939106 |
| 10 | 19039804 |
| 11 | 73394261 |
| 12 | 282923766 |
| 13 | 1090629910 |
| 14 | 4204204919 |
| 15 | 16206551390 |
| 16 | 62473746310 |
| 17 | 240826563663 |
| 18 | 928348880740 |
| 19 | 3578640462085 |
| 20 | 13795101927045 |
| 21 | 53177970281187 |
[102,390,1517,5805,22346,86251,332419,1281181, 4939106,19039804,73394261,282923766,1090629910, 4204204919,16206551390,62473746310,240826563663, 928348880740,3578640462085,13795101927045, 53177970281187] |