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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 30 |
| 4 | 129 |
| 5 | 560 |
| 6 | 2519 |
| 7 | 11486 |
| 8 | 53195 |
| 9 | 248410 |
| 10 | 1170519 |
| 11 | 5547012 |
| 12 | 26430472 |
| 13 | 126464825 |
| 14 | 607337619 |
| 15 | 2925618904 |
| 16 | 14131096096 |
| 17 | 68412200083 |
| 18 | 331879233862 |
| 19 | 1612898604913 |
| 20 | 7851101136329 |
| 21 | 38271628378829 |
| 22 | 186803322830844 |
| 23 | 912850016307839 |
| 24 | 4465556565702484 |
| 25 | 21866158246236156 |
| 26 | 107165459975155635 |
[1,2,8,30,129,560,2519,11486,53195,248410,1170519, 5547012,26430472,126464825,607337619,2925618904, 14131096096,68412200083,331879233862, 1612898604913,7851101136329,38271628378829, 186803322830844,912850016307839,4465556565702484, 21866158246236156,107165459975155635] |