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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 56 |
| 3 | 528 |
| 4 | 4992 |
| 5 | 47232 |
| 6 | 446976 |
| 7 | 4230144 |
| 8 | 40034304 |
| 9 | 378888192 |
| 10 | 3585835008 |
| 11 | 33936703488 |
| 12 | 321180401664 |
| 13 | 3039683936256 |
| 14 | 28767877595136 |
| 15 | 272262116671488 |
| 16 | 2576716337774592 |
| 17 | 24386305253179392 |
| 18 | 230794470931562496 |
[6,56,528,4992,47232,446976,4230144,40034304, 378888192,3585835008,33936703488,321180401664, 3039683936256,28767877595136,272262116671488, 2576716337774592,24386305253179392, 230794470931562496] |