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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 6 |
| 2 | 210 |
| 3 | 30030 |
| 4 | 9699690 |
| 5 | 6469693230 |
| 6 | 7420738134810 |
| 7 | 13082761331670030 |
| 8 | 32589158477190044730 |
| 9 | 117288381359406970983270 |
| 10 | 557940830126698960967415390 |
| 11 | 3217644767340672907899084554130 |
| 12 | 23768741896345550770650537601358310 |
| 13 | 232862364358497360900063316880507363070 |
[1,6,210,30030,9699690,6469693230,7420738134810, 13082761331670030,32589158477190044730, 117288381359406970983270, 557940830126698960967415390, 3217644767340672907899084554130, 23768741896345550770650537601358310, 232862364358497360900063316880507363070] |