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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 114 |
| 5 | 14650 |
| 6 | 368868 |
| 7 | 4216498 |
| 8 | 30222074 |
| 9 | 158918030 |
| 10 | 669582340 |
| 11 | 2387463550 |
| 12 | 7470004954 |
| 13 | 21036576578 |
| 14 | 54315955588 |
| 15 | 130382565930 |
| 16 | 294116445082 |
| 17 | 628800849110 |
| 18 | 1282821452132 |
| 19 | 2511317339446 |
| 20 | 4739431178170 |
[0,0,0,114,14650,368868,4216498,30222074, 158918030,669582340,2387463550,7470004954, 21036576578,54315955588,130382565930,294116445082, 628800849110,1282821452132,2511317339446, 4739431178170] |