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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 4 |
| 6 | 2 |
| 7 | 6 |
| 8 | 20 |
| 9 | 20 |
| 10 | 6 |
| 11 | 16 |
| 12 | 84 |
| 13 | 140 |
| 14 | 84 |
| 15 | 16 |
| 16 | 40 |
| 17 | 324 |
| 18 | 863 |
| 19 | 863 |
| 20 | 324 |
| 21 | 40 |
| 22 | 96 |
| 23 | 1188 |
| 24 | 4962 |
| 25 | 7940 |
| 26 | 4962 |
| 27 | 1188 |
| 28 | 96 |
| 29 | 224 |
| 30 | 4212 |
| 31 | 27313 |
| 32 | 68790 |
| 33 | 68790 |
| 34 | 27313 |
| 35 | 4212 |
| 36 | 224 |
| 37 | 512 |
| 38 | 14580 |
| 39 | 145932 |
| 40 | 573342 |
| 41 | 903332 |
| 42 | 573342 |
| 43 | 145932 |
| 44 | 14580 |
| 45 | 512 |
| 46 | 1152 |
| 47 | 49572 |
| 48 | 763031 |
[0,1,1,2,4,2,6,20,20,6,16,84,140,84,16,40,324,863, 863,324,40,96,1188,4962,7940,4962,1188,96,224, 4212,27313,68790,68790,27313,4212,224,512,14580, 145932,573342,903332,573342,145932,14580,512,1152, 49572,763031] |