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| n | a(n) |
|---|---|
| 3 | 0 |
| 4 | 0 |
| 5 | 5 |
| 6 | 4 |
| 7 | 3 |
| 8 | 23 |
| 9 | 41 |
| 10 | 82 |
| 11 | 240 |
| 12 | 498 |
| 13 | 1273 |
| 14 | 3394 |
| 15 | 7906 |
| 16 | 20304 |
| 17 | 53439 |
| 18 | 134336 |
| 19 | 347586 |
| 20 | 909168 |
| 21 | 2358326 |
| 22 | 6174831 |
| 23 | 16215576 |
| 24 | 42575634 |
| 25 | 112273510 |
| 26 | 296563804 |
| 27 | 784562542 |
| 28 | 2081547706 |
| 29 | 5532770393 |
| 30 | 14734661721 |
| 31 | 39328064226 |
[0,0,5,4,3,23,41,82,240,498,1273,3394,7906,20304, 53439,134336,347586,909168,2358326,6174831, 16215576,42575634,112273510,296563804,784562542, 2081547706,5532770393,14734661721,39328064226] |