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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 16 |
| 3 | 271 |
| 4 | 4591 |
| 5 | 77776 |
| 6 | 1317601 |
| 7 | 22321441 |
| 8 | 378146896 |
| 9 | 6406175791 |
| 10 | 108526841551 |
| 11 | 1838550130576 |
| 12 | 31146825378241 |
| 13 | 527657481299521 |
| 14 | 8939030356713616 |
| 15 | 151435858582831951 |
| 16 | 2565470565551429551 |
| 17 | 43461563755791470416 |
| 18 | 736281113282903567521 |
| 19 | 12473317362053569177441 |
[1,16,271,4591,77776,1317601,22321441,378146896, 6406175791,108526841551,1838550130576, 31146825378241,527657481299521,8939030356713616, 151435858582831951,2565470565551429551, 43461563755791470416,736281113282903567521, 12473317362053569177441] |