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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 23 |
| 3 | 467 |
| 4 | 9355 |
| 5 | 187131 |
| 6 | 3742683 |
| 7 | 74853787 |
| 8 | 1497075995 |
| 9 | 29941520411 |
| 10 | 598830409243 |
| 11 | 11976608186907 |
| 12 | 239532163742235 |
| 13 | 4790643274852891 |
| 14 | 95812865497074203 |
| 15 | 1916257309941516827 |
| 16 | 38325146198830402075 |
| 17 | 766502923976608172571 |
| 18 | 15330058479532163713563 |
| 19 | 306601169590643274795547 |
[0,1,23,467,9355,187131,3742683,74853787, 1497075995,29941520411,598830409243, 11976608186907,239532163742235,4790643274852891, 95812865497074203,1916257309941516827, 38325146198830402075,766502923976608172571, 15330058479532163713563,306601169590643274795547] |