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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 10 |
| 3 | 58 |
| 4 | 402 |
| 5 | 3122 |
| 6 | 26010 |
| 7 | 227050 |
| 8 | 2049186 |
| 9 | 18964194 |
| 10 | 178976426 |
| 11 | 1715905050 |
| 12 | 16665027378 |
| 13 | 163611970066 |
| 14 | 1621103006010 |
| 15 | 16189480081354 |
| 16 | 162791835045698 |
| 17 | 1646810150270914 |
| 18 | 16748008972020554 |
| 19 | 171135004105459194 |
[2,10,58,402,3122,26010,227050,2049186,18964194, 178976426,1715905050,16665027378,163611970066, 1621103006010,16189480081354,162791835045698, 1646810150270914,16748008972020554, 171135004105459194] |