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| n | a(n) |
|---|---|
| 3 | 0 |
| 4 | 2 |
| 5 | 2 |
| 6 | 7 |
| 7 | 13 |
| 8 | 25 |
| 9 | 42 |
| 10 | 81 |
| 11 | 193 |
| 12 | 454 |
| 13 | 1041 |
| 14 | 2502 |
| 15 | 6242 |
| 16 | 13807 |
| 17 | 35326 |
| 18 | 87295 |
| 19 | 209812 |
| 20 | 548575 |
| 21 | 1343566 |
| 22 | 3489028 |
| 23 | 8907422 |
| 24 | 22985251 |
| 25 | 59673055 |
| 26 | 154469560 |
| 27 | 402551592 |
| 28 | 1046972388 |
| 29 | 2729730656 |
| 30 | 7118291151 |
| 31 | 18566002813 |
[0,2,2,7,13,25,42,81,193,454,1041,2502,6242,13807, 35326,87295,209812,548575,1343566,3489028,8907422, 22985251,59673055,154469560,402551592,1046972388, 2729730656,7118291151,18566002813] |