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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 17 |
| 5 | 42 |
| 6 | 104 |
| 7 | 259 |
| 8 | 648 |
| 9 | 1627 |
| 10 | 4098 |
| 11 | 10350 |
| 12 | 26202 |
| 13 | 66471 |
| 14 | 168939 |
| 15 | 430071 |
| 16 | 1096451 |
| 17 | 2799072 |
| 18 | 7154189 |
| 19 | 18305485 |
| 20 | 46885179 |
| 21 | 120195301 |
| 22 | 308393558 |
| 23 | 791882862 |
| 24 | 2034836222 |
| 25 | 5232250537 |
| 26 | 13462265079 |
| 27 | 34657740889 |
| 28 | 89272680921 |
| 29 | 230069128392 |
[1,1,3,7,17,42,104,259,648,1627,4098,10350,26202, 66471,168939,430071,1096451,2799072,7154189, 18305485,46885179,120195301,308393558,791882862, 2034836222,5232250537,13462265079,34657740889, 89272680921,230069128392] |