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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 5 |
| 3 | 68 |
| 4 | 815 |
| 5 | 4172 |
| 6 | 18020 |
| 7 | 62882 |
| 8 | 201551 |
| 9 | 605398 |
| 10 | 1743548 |
| 11 | 4863258 |
| 12 | 13228596 |
| 13 | 35268263 |
| 14 | 92503663 |
| 15 | 239307757 |
| 16 | 611896213 |
| 17 | 1548973531 |
| 18 | 3887082301 |
| 19 | 9679914966 |
| 20 | 23942689688 |
| 21 | 58864085078 |
| 22 | 143936487738 |
| 23 | 350238677040 |
| 24 | 848456244849 |
[0,5,68,815,4172,18020,62882,201551,605398, 1743548,4863258,13228596,35268263,92503663, 239307757,611896213,1548973531,3887082301, 9679914966,23942689688,58864085078,143936487738, 350238677040,848456244849] |