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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 30 |
| 4 | 210 |
| 5 | 2310 |
| 6 | 30030 |
| 7 | 510510 |
| 8 | 9699690 |
| 9 | 223092870 |
| 10 | 6469693230 |
| 11 | 200560490130 |
| 12 | 7420738134810 |
| 13 | 304250263527210 |
| 14 | 13082761331670030 |
| 15 | 614889782588491410 |
| 16 | 32589158477190044730 |
| 17 | 1922760350154212639070 |
| 18 | 117288381359406970983270 |
| 19 | 7858321551080267055879090 |
[1,2,6,30,210,2310,30030,510510,9699690,223092870, 6469693230,200560490130,7420738134810, 304250263527210,13082761331670030, 614889782588491410,32589158477190044730, 1922760350154212639070,117288381359406970983270, 7858321551080267055879090] |