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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 8 |
| 4 | 584 |
| 5 | 5464 |
| 6 | 26360 |
| 7 | 91120 |
| 8 | 252720 |
| 9 | 603696 |
| 10 | 1288592 |
| 11 | 2525400 |
| 12 | 4620728 |
| 13 | 7998984 |
| 14 | 13219528 |
| 15 | 21014336 |
| 16 | 32306400 |
| 17 | 48256608 |
| 18 | 70282656 |
| 19 | 100115880 |
| 20 | 139819944 |
| 21 | 191858360 |
| 22 | 259112216 |
| 23 | 344959120 |
| 24 | 453289232 |
| 25 | 588596368 |
| 26 | 755991600 |
[0,0,8,584,5464,26360,91120,252720,603696,1288592, 2525400,4620728,7998984,13219528,21014336, 32306400,48256608,70282656,100115880,139819944, 191858360,259112216,344959120,453289232,588596368, 755991600] |