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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 840 |
| 3 | 8760 |
| 4 | 41520 |
| 5 | 134544 |
| 6 | 347064 |
| 7 | 768264 |
| 8 | 1523424 |
| 9 | 2780064 |
| 10 | 4754088 |
| 11 | 7715928 |
| 12 | 11996688 |
| 13 | 17994288 |
| 14 | 26179608 |
| 15 | 37102632 |
| 16 | 51398592 |
| 17 | 69794112 |
| 18 | 93113352 |
| 19 | 122284152 |
| 20 | 158344176 |
| 21 | 202447056 |
| 22 | 255868536 |
| 23 | 320012616 |
| 24 | 396417696 |
| 25 | 486762720 |
[0,840,8760,41520,134544,347064,768264,1523424, 2780064,4754088,7715928,11996688,17994288, 26179608,37102632,51398592,69794112,93113352, 122284152,158344176,202447056,255868536,320012616, 396417696,486762720] |