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| n | a(n) |
|---|---|
| 3 | 1 |
| 4 | 2 |
| 5 | 10 |
| 6 | 42 |
| 7 | 209 |
| 8 | 1066 |
| 9 | 5726 |
| 10 | 31688 |
| 11 | 180234 |
| 12 | 1047356 |
| 13 | 6198500 |
| 14 | 37253790 |
| 15 | 226891665 |
| 16 | 1397880330 |
| 17 | 8699804598 |
| 18 | 54629525808 |
| 19 | 345778883678 |
| 20 | 2204263514460 |
| 21 | 14142192816908 |
| 22 | 91263177339092 |
| 23 | 592069697914170 |
| 24 | 3859674384409668 |
| 25 | 25272938482712044 |
[1,2,10,42,209,1066,5726,31688,180234,1047356, 6198500,37253790,226891665,1397880330,8699804598, 54629525808,345778883678,2204263514460, 14142192816908,91263177339092,592069697914170, 3859674384409668,25272938482712044] |