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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 6 |
| 6 | 10 |
| 7 | 36 |
| 8 | 64 |
| 9 | 220 |
| 10 | 468 |
| 11 | 1024 |
| 12 | 2052 |
| 13 | 7590 |
| 14 | 16224 |
| 15 | 50400 |
| 16 | 142800 |
| 17 | 246240 |
| 18 | 510300 |
| 19 | 2261952 |
| 20 | 3545856 |
| 21 | 14152320 |
| 22 | 40986000 |
| 23 | 68428800 |
| 24 | 178293960 |
| 25 | 784274400 |
| 26 | 1526805504 |
| 27 | 2782080000 |
| 28 | 9307872000 |
| 29 | 15858633600 |
| 30 | 28225260000 |
| 31 | 143730892800 |
| 32 | 225167040000 |
[1,1,1,2,6,10,36,64,220,468,1024,2052,7590,16224, 50400,142800,246240,510300,2261952,3545856, 14152320,40986000,68428800,178293960,784274400, 1526805504,2782080000,9307872000,15858633600, 28225260000,143730892800,225167040000] |