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| n | a(n) |
|---|---|
| 8 | 1 |
| 9 | 36 |
| 10 | 750 |
| 11 | 11880 |
| 12 | 159027 |
| 13 | 1899612 |
| 14 | 20912320 |
| 15 | 216627840 |
| 16 | 2141764053 |
| 17 | 20415995028 |
| 18 | 189036065010 |
| 19 | 1709751003480 |
| 20 | 15170932662679 |
| 21 | 132511015347084 |
| 22 | 1142399079991620 |
| 23 | 9741955019900400 |
| 24 | 82318282158320505 |
| 25 | 690223721118368580 |
| 26 | 5749622251945664950 |
[1,36,750,11880,159027,1899612,20912320,216627840, 2141764053,20415995028,189036065010,1709751003480, 15170932662679,132511015347084,1142399079991620, 9741955019900400,82318282158320505, 690223721118368580,5749622251945664950] |