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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 14 |
| 5 | 42 |
| 6 | 203 |
| 7 | 724 |
| 8 | 3100 |
| 9 | 11844 |
| 10 | 48517 |
| 11 | 190358 |
| 12 | 766922 |
| 13 | 3039726 |
| 14 | 12169871 |
| 15 | 48422248 |
| 16 | 193402552 |
| 17 | 770650824 |
| 18 | 3075264841 |
| 19 | 12260822378 |
| 20 | 48909765254 |
| 21 | 195040307826 |
| 22 | 777935950355 |
| 23 | 3102468986044 |
| 24 | 12373867741396 |
| 25 | 49349446870668 |
[0,1,2,14,42,203,724,3100,11844,48517,190358, 766922,3039726,12169871,48422248,193402552, 770650824,3075264841,12260822378,48909765254, 195040307826,777935950355,3102468986044, 12373867741396,49349446870668] |