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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 127 |
| 8 | 1568 |
| 9 | 17221 |
| 10 | 157710 |
| 11 | 1360107 |
| 12 | 11104632 |
| 13 | 87999275 |
| 14 | 681209386 |
| 15 | 5192306420 |
| 16 | 39117179936 |
| 17 | 292250754994 |
| 18 | 2169869100416 |
| 19 | 16036792568508 |
| 20 | 118115950230120 |
| 21 | 867736883991669 |
| 22 | 6362604049648708 |
| 23 | 46586411156710601 |
| 24 | 340735507632772936 |
[0,0,0,0,0,0,0,127,1568,17221,157710,1360107, 11104632,87999275,681209386,5192306420, 39117179936,292250754994,2169869100416, 16036792568508,118115950230120,867736883991669, 6362604049648708,46586411156710601, 340735507632772936] |