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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 30 |
| 4 | 406 |
| 5 | 6336 |
| 6 | 107415 |
| 7 | 1922310 |
| 8 | 35739990 |
| 9 | 683593902 |
| 10 | 13364444808 |
| 11 | 265869803598 |
| 12 | 5364752267064 |
| 13 | 109533577804350 |
| 14 | 2258715717810522 |
| 15 | 46974966620274810 |
| 16 | 984153696477302700 |
| 17 | 20751365954898103338 |
| 18 | 440033530633057730880 |
| 19 | 9377869165352931696930 |
[1,3,30,406,6336,107415,1922310,35739990, 683593902,13364444808,265869803598,5364752267064, 109533577804350,2258715717810522, 46974966620274810,984153696477302700, 20751365954898103338,440033530633057730880, 9377869165352931696930] |