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| n | a(n) |
|---|---|
| 4 | 210 |
| 5 | 2772 |
| 6 | 19404 |
| 7 | 96096 |
| 8 | 378378 |
| 9 | 1261260 |
| 10 | 3699696 |
| 11 | 9801792 |
| 12 | 23891868 |
| 13 | 54318264 |
| 14 | 116396280 |
| 15 | 237025152 |
| 16 | 461705244 |
| 17 | 864913896 |
| 18 | 1565082288 |
| 19 | 2745758400 |
| 20 | 4684950270 |
| 21 | 7795127340 |
| 22 | 12676924260 |
| 23 | 20190250080 |
| 24 | 31547265750 |
| 25 | 48432564180 |
| 26 | 73156880160 |
| 27 | 108851783040 |
[210,2772,19404,96096,378378,1261260,3699696, 9801792,23891868,54318264,116396280,237025152, 461705244,864913896,1565082288,2745758400, 4684950270,7795127340,12676924260,20190250080, 31547265750,48432564180,73156880160,108851783040] |