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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 2 |
| 5 | 3 |
| 6 | 0 |
| 7 | 6 |
| 8 | 30 |
| 9 | 15 |
| 10 | 0 |
| 11 | 20 |
| 12 | 308 |
| 13 | 420 |
| 14 | 105 |
| 15 | 0 |
| 16 | 70 |
| 17 | 3420 |
| 18 | 10080 |
| 19 | 6300 |
| 20 | 945 |
| 21 | 0 |
| 22 | 252 |
| 23 | 41052 |
| 24 | 242220 |
| 25 | 291060 |
| 26 | 103950 |
| 27 | 10395 |
| 28 | 0 |
| 29 | 924 |
| 30 | 523432 |
| 31 | 6048042 |
| 32 | 12672660 |
| 33 | 8198190 |
| 34 | 1891890 |
| 35 | 135135 |
| 36 | 0 |
| 37 | 3432 |
| 38 | 6965520 |
| 39 | 158012400 |
| 40 | 552071520 |
| 41 | 581981400 |
| 42 | 234594360 |
| 43 | 37837800 |
| 44 | 2027025 |
[1,0,1,0,2,3,0,6,30,15,0,20,308,420,105,0,70,3420, 10080,6300,945,0,252,41052,242220,291060,103950, 10395,0,924,523432,6048042,12672660,8198190, 1891890,135135,0,3432,6965520,158012400,552071520, 581981400,234594360,37837800,2027025] |