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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 88 |
| 4 | 1361 |
| 5 | 28182 |
| 6 | 726889 |
| 7 | 22414988 |
| 8 | 803913441 |
| 9 | 32867765002 |
| 10 | 1508608850249 |
| 11 | 76804271962848 |
| 12 | 4294870015118641 |
| 13 | 261673684619584862 |
| 14 | 17252970318529474089 |
| 15 | 1223896705010751194068 |
| 16 | 92946073511938131386561 |
| 17 | 7523666291578066678172562 |
| 18 | 646658551118777059833155209 |
[1,2,9,88,1361,28182,726889,22414988,803913441, 32867765002,1508608850249,76804271962848, 4294870015118641,261673684619584862, 17252970318529474089,1223896705010751194068, 92946073511938131386561,7523666291578066678172562, 646658551118777059833155209] |