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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 2 |
| 3 | 4 |
| 4 | 6 |
| 5 | 8 |
| 6 | 17 |
| 7 | 62 |
| 8 | 97 |
| 9 | 362 |
| 10 | 1324 |
| 11 | 3868 |
| 12 | 13138 |
| 13 | 92566 |
| 14 | 270599 |
| 15 | 1645369 |
| 16 | 11553340 |
| 17 | 61799175 |
| 18 | 385381600 |
| 19 | 4833634814 |
| 20 | 26435310212 |
| 21 | 299198500876 |
| 22 | 3860046376506 |
| 23 | 38367622605338 |
| 24 | 439015544648715 |
| 25 | 10375069938961300 |
[1,2,2,4,6,8,17,62,97,362,1324,3868,13138,92566, 270599,1645369,11553340,61799175,385381600, 4833634814,26435310212,299198500876,3860046376506, 38367622605338,439015544648715,10375069938961300] |