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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 16 |
| 5 | 47 |
| 6 | 157 |
| 7 | 507 |
| 8 | 1714 |
| 9 | 6074 |
| 10 | 21360 |
| 11 | 77241 |
| 12 | 284811 |
| 13 | 1051900 |
| 14 | 3954103 |
| 15 | 15003471 |
| 16 | 57201331 |
| 17 | 220534963 |
| 18 | 855038657 |
| 19 | 3332650936 |
| 20 | 13084082094 |
| 21 | 51582007825 |
| 22 | 204327262149 |
| 23 | 813393343533 |
| 24 | 3249188679150 |
| 25 | 13031012456908 |
| 26 | 52450320596046 |
| 27 | 211746189564692 |
| 28 | 857602778653967 |
| 29 | 3483222763555429 |
[1,1,2,6,16,47,157,507,1714,6074,21360,77241, 284811,1051900,3954103,15003471,57201331, 220534963,855038657,3332650936,13084082094, 51582007825,204327262149,813393343533, 3249188679150,13031012456908,52450320596046, 211746189564692,857602778653967,3483222763555429] |