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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 1 |
| 6 | 11 |
| 7 | 13 |
| 8 | 82 |
| 9 | 162 |
| 10 | 929 |
| 11 | 1369 |
| 12 | 13718 |
| 13 | 16421 |
| 14 | 124689 |
| 15 | 355792 |
| 16 | 1356698 |
| 17 | 2555043 |
| 18 | 25933641 |
| 19 | 32931815 |
| 20 | 283329802 |
| 21 | 720489742 |
| 22 | 3308253663 |
| 23 | 5763641923 |
| 24 | 60874684720 |
| 25 | 93543112675 |
| 26 | 600086794431 |
[0,0,0,1,1,11,13,82,162,929,1369,13718,16421, 124689,355792,1356698,2555043,25933641,32931815, 283329802,720489742,3308253663,5763641923, 60874684720,93543112675,600086794431] |