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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 20 |
| 3 | 45 |
| 4 | 3240 |
| 5 | 42525 |
| 6 | 8292375 |
| 7 | 1915538625 |
| 8 | 312615903600 |
| 9 | 488462349375 |
| 10 | 769328200265625 |
| 11 | 96473756313309375 |
| 12 | 8682638068197843750 |
| 13 | 9086380738369043484375 |
| 14 | 527010082825404522093750 |
| 15 | 5081882941530686463046875 |
| 16 | 33712429605969723121012500000 |
| 17 | 21652861427859241228317809765625 |
[2,20,45,3240,42525,8292375,1915538625, 312615903600,488462349375,769328200265625, 96473756313309375,8682638068197843750, 9086380738369043484375,527010082825404522093750, 5081882941530686463046875, 33712429605969723121012500000, 21652861427859241228317809765625] |