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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 28 |
| 4 | 124 |
| 5 | 506 |
| 6 | 2325 |
| 7 | 10121 |
| 8 | 47466 |
| 9 | 214129 |
| 10 | 1017164 |
| 11 | 4692031 |
| 12 | 22482423 |
| 13 | 105282324 |
| 14 | 507640379 |
| 15 | 2402998152 |
| 16 | 11641232260 |
| 17 | 55550981755 |
| 18 | 270101725432 |
| 19 | 1296919941414 |
| 20 | 6324377801704 |
| 21 | 30516294036669 |
| 22 | 149166338438914 |
| 23 | 722606464011632 |
| 24 | 3539150056696503 |
| 25 | 17200434795171516 |
| 26 | 84383788322559388 |
[1,2,8,28,124,506,2325,10121,47466,214129,1017164, 4692031,22482423,105282324,507640379,2402998152, 11641232260,55550981755,270101725432, 1296919941414,6324377801704,30516294036669, 149166338438914,722606464011632,3539150056696503, 17200434795171516,84383788322559388] |