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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 22 |
| 3 | 208 |
| 4 | 1939 |
| 5 | 17406 |
| 6 | 149057 |
| 7 | 1224092 |
| 8 | 9717407 |
| 9 | 75078490 |
| 10 | 567486429 |
| 11 | 4212636472 |
| 12 | 30802884219 |
| 13 | 222362166198 |
| 14 | 1587624277241 |
| 15 | 11227499711316 |
| 16 | 78737492563415 |
| 17 | 548110879578258 |
| 18 | 3790518591777685 |
| 19 | 26059838687117808 |
[0,22,208,1939,17406,149057,1224092,9717407, 75078490,567486429,4212636472,30802884219, 222362166198,1587624277241,11227499711316, 78737492563415,548110879578258,3790518591777685, 26059838687117808] |