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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 83 |
| 4 | 299 |
| 5 | 1263 |
| 6 | 6076 |
| 7 | 31307 |
| 8 | 168561 |
| 9 | 936161 |
| 10 | 5321611 |
| 11 | 30804795 |
| 12 | 180939408 |
| 13 | 1075636912 |
| 14 | 6459103704 |
| 15 | 39120216196 |
| 16 | 238692219923 |
| 17 | 1465783144605 |
| 18 | 9052278085129 |
| 19 | 56185368932615 |
| 20 | 350293215459915 |
| 21 | 2192731008315015 |
| 22 | 13775745283576920 |
| 23 | 86831135890324875 |
[0,0,0,83,299,1263,6076,31307,168561,936161, 5321611,30804795,180939408,1075636912,6459103704, 39120216196,238692219923,1465783144605, 9052278085129,56185368932615,350293215459915, 2192731008315015,13775745283576920, 86831135890324875] |