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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 21 |
| 3 | 148 |
| 4 | 1038 |
| 5 | 7269 |
| 6 | 50883 |
| 7 | 356182 |
| 8 | 2493276 |
| 9 | 17452935 |
| 10 | 122170545 |
| 11 | 855193816 |
| 12 | 5986356714 |
| 13 | 41904497001 |
| 14 | 293331479007 |
| 15 | 2053320353050 |
| 16 | 14373242471352 |
| 17 | 100612697299467 |
| 18 | 704288881096269 |
| 19 | 4930022167673884 |
[3,21,148,1038,7269,50883,356182,2493276,17452935, 122170545,855193816,5986356714,41904497001, 293331479007,2053320353050,14373242471352, 100612697299467,704288881096269,4930022167673884] |