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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 12 |
| 4 | 29 |
| 5 | 176 |
| 6 | 198 |
| 7 | 1608 |
| 8 | 3519 |
| 9 | 11604 |
| 10 | 12500 |
| 11 | 152720 |
| 12 | 160970 |
| 13 | 2292000 |
| 14 | 2417700 |
| 15 | 2549904 |
| 16 | 5336115 |
| 17 | 97630080 |
| 18 | 101271000 |
| 19 | 2055670560 |
| 20 | 2125864116 |
| 21 | 2209916016 |
| 22 | 2291367000 |
| 23 | 55764302880 |
| 24 | 57138304410 |
| 25 | 297081542208 |
[1,3,12,29,176,198,1608,3519,11604,12500,152720, 160970,2292000,2417700,2549904,5336115,97630080, 101271000,2055670560,2125864116,2209916016, 2291367000,55764302880,57138304410,297081542208] |