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| n | a(n) |
|---|---|
| 2 | 0 |
| 3 | 1 |
| 4 | 3 |
| 5 | 19 |
| 6 | 97 |
| 7 | 678 |
| 8 | 5098 |
| 9 | 52170 |
| 10 | 582342 |
| 11 | 8221455 |
| 12 | 125339157 |
| 13 | 2312227461 |
| 14 | 45664819407 |
| 15 | 1056675718876 |
| 16 | 26022340062564 |
| 17 | 734233350312484 |
| 18 | 21939269071805596 |
| 19 | 738213020202917421 |
| 20 | 26196923530426606903 |
| 21 | 1032994592794340235015 |
| 22 | 42808941242555092330701 |
[0,1,3,19,97,678,5098,52170,582342,8221455, 125339157,2312227461,45664819407,1056675718876, 26022340062564,734233350312484,21939269071805596, 738213020202917421,26196923530426606903, 1032994592794340235015,42808941242555092330701] |