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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 13 |
| 6 | 34 |
| 7 | 91 |
| 8 | 251 |
| 9 | 709 |
| 10 | 2035 |
| 11 | 5913 |
| 12 | 17366 |
| 13 | 51483 |
| 14 | 153858 |
| 15 | 463001 |
| 16 | 1401751 |
| 17 | 4266619 |
| 18 | 13048709 |
| 19 | 40078032 |
| 20 | 123570957 |
| 21 | 382331356 |
| 22 | 1186699353 |
| 23 | 3694028136 |
| 24 | 11529606672 |
| 25 | 36073811897 |
| 26 | 113123222246 |
| 27 | 355485228001 |
| 28 | 1119275386080 |
| 29 | 3530531671842 |
[1,1,1,2,5,13,34,91,251,709,2035,5913,17366,51483, 153858,463001,1401751,4266619,13048709,40078032, 123570957,382331356,1186699353,3694028136, 11529606672,36073811897,113123222246,355485228001, 1119275386080,3530531671842] |