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| n | a(n) |
|---|---|
| 0 | -1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 4 |
| 6 | 19 |
| 7 | 111 |
| 8 | 760 |
| 9 | 5976 |
| 10 | 53062 |
| 11 | 524919 |
| 12 | 5723493 |
| 13 | 68181821 |
| 14 | 880916799 |
| 15 | 12267980944 |
| 16 | 183181681783 |
| 17 | 2919228642272 |
| 18 | 49452334100912 |
| 19 | 887356817041401 |
| 20 | 16812532278748455 |
| 21 | 335401627901612613 |
| 22 | 7027324571812426900 |
| 23 | 154279299692901768147 |
| 24 | 3541671282222287112486 |
[-1,0,0,0,1,4,19,111,760,5976,53062,524919, 5723493,68181821,880916799,12267980944, 183181681783,2919228642272,49452334100912, 887356817041401,16812532278748455, 335401627901612613,7027324571812426900, 154279299692901768147,3541671282222287112486] |