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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 15 |
| 5 | 330 |
| 6 | 50388 |
| 7 | 225792840 |
| 8 | 202355008436035 |
| 9 | 1051518440185020535448910 |
| 10 | 6295006026005594769305465540976338825800 |
| 11 | 250690498666352364302787619036257555981545221373940020366174361300 |
| 12 | 76323919118339641225070197870691336391548146418602896138838604379490915124967820851616650659494440178513500 |
[1,1,3,15,330,50388,225792840,202355008436035, 1051518440185020535448910, 6295006026005594769305465540976338825800, 25069049866635236430278761903625755598154522137394\ 0020366174361300, 76323919118339641225070197870691336391548146418602\ 89613883860437949091512496782085161665065949444017\ 8513500] |