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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 1346 |
| 3 | 41852 |
| 4 | 491892 |
| 5 | 3436102 |
| 6 | 17232446 |
| 7 | 68544440 |
| 8 | 229551288 |
| 9 | 672922218 |
| 10 | 1773763178 |
| 11 | 4286374004 |
| 12 | 9634559948 |
| 13 | 20367690798 |
| 14 | 40850961478 |
| 15 | 78277647728 |
| 16 | 144113836976 |
| 17 | 256112415570 |
| 18 | 441063276882 |
| 19 | 738481048172 |
| 20 | 1205470385252 |
[2,1346,41852,491892,3436102,17232446,68544440, 229551288,672922218,1773763178,4286374004, 9634559948,20367690798,40850961478,78277647728, 144113836976,256112415570,441063276882, 738481048172,1205470385252] |