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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 3 |
| 4 | 21 |
| 5 | 185 |
| 6 | 2101 |
| 7 | 29127 |
| 8 | 478297 |
| 9 | 9090909 |
| 10 | 196495641 |
| 11 | 4762874171 |
| 12 | 128011456717 |
| 13 | 3779594158353 |
| 14 | 121637191772461 |
| 15 | 4238682002231055 |
| 16 | 159023502861656433 |
| 17 | 6391554268241802725 |
| 18 | 274019342889240109297 |
[1,0,1,3,21,185,2101,29127,478297,9090909, 196495641,4762874171,128011456717,3779594158353, 121637191772461,4238682002231055, 159023502861656433,6391554268241802725, 274019342889240109297] |