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| n | a(n) |
|---|---|
| 1 | 1276 |
| 2 | 3744 |
| 3 | 13750 |
| 4 | 34288 |
| 5 | 110274 |
| 6 | 313060 |
| 7 | 1059410 |
| 8 | 2852400 |
| 9 | 9387554 |
| 10 | 25937988 |
| 11 | 86158450 |
| 12 | 235806192 |
| 13 | 779991734 |
| 14 | 2143722636 |
| 15 | 7102177066 |
| 16 | 19487328696 |
| 17 | 64517987030 |
| 18 | 177151900644 |
| 19 | 586666746358 |
| 20 | 1610397251352 |
| 21 | 5332485179726 |
[1276,3744,13750,34288,110274,313060,1059410, 2852400,9387554,25937988,86158450,235806192, 779991734,2143722636,7102177066,19487328696, 64517987030,177151900644,586666746358, 1610397251352,5332485179726] |