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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 7 |
| 4 | 4 |
| 5 | 21 |
| 6 | 13 |
| 7 | 71 |
| 8 | 44 |
| 9 | 241 |
| 10 | 149 |
| 11 | 815 |
| 12 | 504 |
| 13 | 2757 |
| 14 | 1705 |
| 15 | 9327 |
| 16 | 5768 |
| 17 | 31553 |
| 18 | 19513 |
| 19 | 106743 |
| 20 | 66012 |
| 21 | 361109 |
| 22 | 223317 |
| 23 | 1221623 |
| 24 | 755476 |
| 25 | 4132721 |
| 26 | 2555757 |
| 27 | 13980895 |
| 28 | 8646064 |
| 29 | 47297029 |
| 30 | 29249425 |
| 31 | 160004703 |
| 32 | 98950096 |
| 33 | 541292033 |
| 34 | 334745777 |
[0,1,1,7,4,21,13,71,44,241,149,815,504,2757,1705, 9327,5768,31553,19513,106743,66012,361109,223317, 1221623,755476,4132721,2555757,13980895,8646064, 47297029,29249425,160004703,98950096,541292033, 334745777] |