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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 7 |
| 5 | 13 |
| 6 | 34 |
| 7 | 73 |
| 8 | 209 |
| 9 | 501 |
| 10 | 1546 |
| 11 | 4051 |
| 12 | 13327 |
| 13 | 37633 |
| 14 | 130922 |
| 15 | 394353 |
| 16 | 1441729 |
| 17 | 4596553 |
| 18 | 17572114 |
| 19 | 58941091 |
| 20 | 234662231 |
| 21 | 824073141 |
| 22 | 3405357682 |
| 23 | 12470162233 |
| 24 | 53334454417 |
| 25 | 202976401213 |
| 26 | 896324308634 |
| 27 | 3535017524403 |
| 28 | 16083557845279 |
| 29 | 65573803186921 |
[1,1,2,3,7,13,34,73,209,501,1546,4051,13327,37633, 130922,394353,1441729,4596553,17572114,58941091, 234662231,824073141,3405357682,12470162233, 53334454417,202976401213,896324308634, 3535017524403,16083557845279,65573803186921] |