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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 29 |
| 4 | 182 |
| 5 | 1198 |
| 6 | 8142 |
| 7 | 56620 |
| 8 | 400598 |
| 9 | 2872754 |
| 10 | 20824778 |
| 11 | 152303410 |
| 12 | 1122149800 |
| 13 | 8319825040 |
| 14 | 62017475600 |
| 15 | 464452683432 |
| 16 | 3492568119566 |
| 17 | 26358270711370 |
| 18 | 199565061455634 |
| 19 | 1515311001158482 |
| 20 | 11535716330003876 |
| 21 | 88025068713285476 |
| 22 | 673124069796140900 |
[1,1,5,29,182,1198,8142,56620,400598,2872754, 20824778,152303410,1122149800,8319825040, 62017475600,464452683432,3492568119566, 26358270711370,199565061455634,1515311001158482, 11535716330003876,88025068713285476, 673124069796140900] |