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| n | a(n) |
|---|---|
| 1 | 20 |
| 2 | 12 |
| 3 | 56 |
| 4 | 550 |
| 5 | 572 |
| 6 | 108 |
| 7 | 860 |
| 8 | 952 |
| 9 | 1232 |
| 10 | 6328 |
| 11 | 3708 |
| 12 | 40540 |
| 13 | 37072 |
| 14 | 79288 |
| 15 | 327260 |
| 16 | 357112 |
| 17 | 302000 |
| 18 | 527296 |
| 19 | 1764056 |
| 20 | 6506512 |
| 21 | 38559776 |
| 22 | 21893248 |
| 23 | 42257216 |
| 24 | 167771740 |
| 25 | 90798560 |
| 26 | 469761208 |
| 27 | 508198064 |
| 28 | 490304800 |
| 29 | 1353048560 |
| 30 | 2951488480 |
| 31 | 5067417200 |
[20,12,56,550,572,108,860,952,1232,6328,3708, 40540,37072,79288,327260,357112,302000,527296, 1764056,6506512,38559776,21893248,42257216, 167771740,90798560,469761208,508198064,490304800, 1353048560,2951488480,5067417200] |