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| n | a(n) |
|---|---|
| 4 | 21 |
| 5 | 483 |
| 6 | 6468 |
| 7 | 66066 |
| 8 | 570570 |
| 9 | 4390386 |
| 10 | 31039008 |
| 11 | 205633428 |
| 12 | 1293938646 |
| 13 | 7808250450 |
| 14 | 45510945480 |
| 15 | 257611421340 |
| 16 | 1422156202740 |
| 17 | 7683009544980 |
| 18 | 40729207226400 |
| 19 | 212347275857640 |
| 20 | 1090848505817070 |
| 21 | 5530195966465170 |
| 22 | 27704671055301240 |
| 23 | 137308238124957900 |
| 24 | 673903972248687180 |
[21,483,6468,66066,570570,4390386,31039008, 205633428,1293938646,7808250450,45510945480, 257611421340,1422156202740,7683009544980, 40729207226400,212347275857640,1090848505817070, 5530195966465170,27704671055301240, 137308238124957900,673903972248687180] |