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| n | a(n) |
|---|---|
| 12 | 91 |
| 13 | 1470 |
| 14 | 12600 |
| 15 | 76160 |
| 16 | 364140 |
| 17 | 1465128 |
| 18 | 5155080 |
| 19 | 16279200 |
| 20 | 47006190 |
| 21 | 125847260 |
| 22 | 315762216 |
| 23 | 748843200 |
| 24 | 1690097500 |
| 25 | 3650610600 |
| 26 | 7582037400 |
| 27 | 15201516960 |
| 28 | 29520803025 |
| 29 | 55688330250 |
| 30 | 102301525200 |
| 31 | 183413260800 |
| 32 | 321546372840 |
| 33 | 552150337200 |
| 34 | 930092814000 |
[91,1470,12600,76160,364140,1465128,5155080, 16279200,47006190,125847260,315762216,748843200, 1690097500,3650610600,7582037400,15201516960, 29520803025,55688330250,102301525200,183413260800, 321546372840,552150337200,930092814000] |