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| n | a(n) |
|---|---|
| 3 | 0 |
| 4 | 4 |
| 5 | 0 |
| 6 | 2 |
| 7 | 0 |
| 8 | 12 |
| 9 | 8 |
| 10 | 124 |
| 11 | 124 |
| 12 | 568 |
| 13 | 938 |
| 14 | 2504 |
| 15 | 5920 |
| 16 | 15036 |
| 17 | 38622 |
| 18 | 94718 |
| 19 | 244900 |
| 20 | 618326 |
| 21 | 1536234 |
| 22 | 4099758 |
| 23 | 9977262 |
| 24 | 26982442 |
| 25 | 66352956 |
| 26 | 179514926 |
| 27 | 447677038 |
| 28 | 1206219808 |
| 29 | 3053871710 |
| 30 | 8159293202 |
| 31 | 20968150036 |
| 32 | 55708043068 |
[0,4,0,2,0,12,8,124,124,568,938,2504,5920,15036, 38622,94718,244900,618326,1536234,4099758,9977262, 26982442,66352956,179514926,447677038,1206219808, 3053871710,8159293202,20968150036,55708043068] |