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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 12 |
| 4 | 72 |
| 5 | 576 |
| 6 | 5184 |
| 7 | 57024 |
| 8 | 684288 |
| 9 | 9580032 |
| 10 | 153280512 |
| 11 | 2605768704 |
| 12 | 49509605376 |
| 13 | 1039701712896 |
| 14 | 22873437683712 |
| 15 | 548962504409088 |
| 16 | 13724062610227200 |
| 17 | 370549690476134400 |
| 18 | 10745941023807897600 |
| 19 | 322378230714236928000 |
| 20 | 10316103382855581696000 |
| 21 | 340431411634234195968000 |
| 22 | 11915099407198196858880000 |
| 23 | 440858678066333283778560000 |
| 24 | 16752629766520664783585280000 |
| 25 | 670105190660826591343411200000 |
[1,3,12,72,576,5184,57024,684288,9580032, 153280512,2605768704,49509605376,1039701712896, 22873437683712,548962504409088,13724062610227200, 370549690476134400,10745941023807897600, 322378230714236928000,10316103382855581696000, 340431411634234195968000, 11915099407198196858880000, 440858678066333283778560000, 16752629766520664783585280000, 670105190660826591343411200000] |