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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 3 |
| 7 | 5 |
| 8 | 11 |
| 9 | 37 |
| 10 | 83 |
| 11 | 274 |
| 12 | 1217 |
| 13 | 6161 |
| 14 | 22833 |
| 15 | 165713 |
| 16 | 1249441 |
| 17 | 9434290 |
| 18 | 68570323 |
| 19 | 1013908933 |
| 20 | 11548470571 |
| 21 | 142844426789 |
| 22 | 2279343327171 |
| 23 | 57760865728994 |
| 24 | 979023970244321 |
| 25 | 23510036246274433 |
| 26 | 771025645214210753 |
[1,1,1,1,1,2,3,5,11,37,83,274,1217,6161,22833, 165713,1249441,9434290,68570323,1013908933, 11548470571,142844426789,2279343327171, 57760865728994,979023970244321,23510036246274433, 771025645214210753] |