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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 4 |
| 5 | 24 |
| 6 | 84 |
| 7 | 224 |
| 8 | 504 |
| 9 | 1008 |
| 10 | 1848 |
| 11 | 3168 |
| 12 | 5148 |
| 13 | 8008 |
| 14 | 12012 |
| 15 | 17472 |
| 16 | 24752 |
| 17 | 34272 |
| 18 | 46512 |
| 19 | 62016 |
| 20 | 81396 |
| 21 | 105336 |
| 22 | 134596 |
| 23 | 170016 |
| 24 | 212520 |
| 25 | 263120 |
| 26 | 322920 |
| 27 | 393120 |
| 28 | 475020 |
| 29 | 570024 |
| 30 | 679644 |
| 31 | 805504 |
| 32 | 949344 |
| 33 | 1113024 |
| 34 | 1298528 |
| 35 | 1507968 |
| 36 | 1743588 |
| 37 | 2007768 |
| 38 | 2303028 |
[0,0,0,0,4,24,84,224,504,1008,1848,3168,5148,8008, 12012,17472,24752,34272,46512,62016,81396,105336, 134596,170016,212520,263120,322920,393120,475020, 570024,679644,805504,949344,1113024,1298528, 1507968,1743588,2007768,2303028] |