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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 372 |
| 3 | 8862 |
| 4 | 148800 |
| 5 | 2096886 |
| 6 | 26922756 |
| 7 | 332847654 |
| 8 | 4138425600 |
| 9 | 53260806102 |
| 10 | 715168132932 |
| 11 | 9918365312598 |
| 12 | 139707565435200 |
| 13 | 1971543518031366 |
| 14 | 27670255890476676 |
| 15 | 385457279875640742 |
| 16 | 5335884957031756800 |
| 17 | 73579514340980051958 |
| 18 | 1013129779240735463748 |
[6,372,8862,148800,2096886,26922756,332847654, 4138425600,53260806102,715168132932,9918365312598, 139707565435200,1971543518031366, 27670255890476676,385457279875640742, 5335884957031756800,73579514340980051958, 1013129779240735463748] |