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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 33 |
| 4 | 149 |
| 5 | 671 |
| 6 | 3124 |
| 7 | 14572 |
| 8 | 69027 |
| 9 | 327738 |
| 10 | 1568883 |
| 11 | 7526367 |
| 12 | 36282157 |
| 13 | 175229271 |
| 14 | 848963109 |
| 15 | 4119569655 |
| 16 | 20033898783 |
| 17 | 97555323988 |
| 18 | 475811775727 |
| 19 | 2323275614661 |
| 20 | 11358048112728 |
| 21 | 55579446613429 |
| 22 | 272240840947922 |
| 23 | 1334566048873148 |
| 24 | 6547544693115974 |
| 25 | 32145195316547195 |
| 26 | 157924212566811068 |
[1,2,8,33,149,671,3124,14572,69027,327738,1568883, 7526367,36282157,175229271,848963109,4119569655, 20033898783,97555323988,475811775727, 2323275614661,11358048112728,55579446613429, 272240840947922,1334566048873148,6547544693115974, 32145195316547195,157924212566811068] |