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| n | a(n) |
|---|---|
| 6 | 1 |
| 7 | 0 |
| 8 | 0 |
| 9 | 0 |
| 10 | 0 |
| 11 | 0 |
| 12 | 923 |
| 13 | 3430 |
| 14 | 6004 |
| 15 | 10008 |
| 16 | 16014 |
| 17 | 24750 |
| 18 | 17153135 |
| 19 | 139520497 |
| 20 | 747544744 |
| 21 | 2907714483 |
| 22 | 9788905840 |
| 23 | 30236892651 |
| 24 | 2389382438831 |
| 25 | 33146052783575 |
| 26 | 291048293120402 |
| 27 | 2033077226586965 |
| 28 | 11881137473504364 |
| 29 | 61473838487159979 |
| 30 | 1656802388288612691 |
[1,0,0,0,0,0,923,3430,6004,10008,16014,24750, 17153135,139520497,747544744,2907714483, 9788905840,30236892651,2389382438831, 33146052783575,291048293120402,2033077226586965, 11881137473504364,61473838487159979, 1656802388288612691] |