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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 16 |
| 4 | 130 |
| 5 | 1416 |
| 6 | 19236 |
| 7 | 312512 |
| 8 | 5906502 |
| 9 | 127313320 |
| 10 | 3082645951 |
| 11 | 82848394752 |
| 12 | 2447576485341 |
| 13 | 78846484722208 |
| 14 | 2750891289611235 |
| 15 | 103344880800464896 |
| 16 | 4159577854374314795 |
| 17 | 178587276548655542112 |
| 18 | 8147334149686335230068 |
[1,3,16,130,1416,19236,312512,5906502,127313320, 3082645951,82848394752,2447576485341, 78846484722208,2750891289611235, 103344880800464896,4159577854374314795, 178587276548655542112,8147334149686335230068] |