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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 11 |
| 3 | 40 |
| 4 | 146 |
| 5 | 533 |
| 6 | 1946 |
| 7 | 7105 |
| 8 | 25941 |
| 9 | 94714 |
| 10 | 345812 |
| 11 | 1262601 |
| 12 | 4609907 |
| 13 | 16831321 |
| 14 | 61453163 |
| 15 | 224372837 |
| 16 | 819212023 |
| 17 | 2991040928 |
| 18 | 10920647625 |
| 19 | 39872588647 |
| 20 | 145579582824 |
| 21 | 531528442330 |
| 22 | 1940673819263 |
| 23 | 7085631873740 |
| 24 | 25870488153041 |
| 25 | 94456241758347 |
[1,3,11,40,146,533,1946,7105,25941,94714,345812, 1262601,4609907,16831321,61453163,224372837, 819212023,2991040928,10920647625,39872588647, 145579582824,531528442330,1940673819263, 7085631873740,25870488153041,94456241758347] |