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| n | a(n) |
|---|---|
| 9 | 1764322560 |
| 10 | 268497815040 |
| 11 | 23638153069440 |
| 12 | 1582270134681600 |
| 13 | 89523597871058400 |
| 14 | 4521537191138385600 |
| 15 | 210558053896067770200 |
| 16 | 9231136974969952417200 |
| 17 | 386479930120038746283600 |
| 18 | 15609810973119409265234400 |
| 19 | 612788961533595085909010880 |
| 20 | 23513250306172521375772885440 |
[1764322560,268497815040,23638153069440, 1582270134681600,89523597871058400, 4521537191138385600,210558053896067770200, 9231136974969952417200,386479930120038746283600, 15609810973119409265234400, 612788961533595085909010880, 23513250306172521375772885440] |