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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 60 |
| 3 | 0 |
| 4 | 1740 |
| 5 | 0 |
| 6 | 32480 |
| 7 | 0 |
| 8 | 438540 |
| 9 | 0 |
| 10 | 4563672 |
| 11 | 0 |
| 12 | 38099040 |
| 13 | 0 |
| 14 | 262336320 |
| 15 | 1073741824 |
| 16 | 1521151500 |
| 17 | 0 |
| 18 | 7553367900 |
| 19 | 32212254720 |
| 20 | 32592806520 |
| 21 | 0 |
| 22 | 123909200160 |
| 23 | 467077693440 |
| 24 | 420775407200 |
| 25 | 0 |
| 26 | 1294230433560 |
| 27 | 4391604060160 |
| 28 | 3655476494400 |
| 29 | 0 |
| 30 | 9600504649920 |
[1,0,60,0,1740,0,32480,0,438540,0,4563672,0, 38099040,0,262336320,1073741824,1521151500,0, 7553367900,32212254720,32592806520,0,123909200160, 467077693440,420775407200,0,1294230433560, 4391604060160,3655476494400,0,9600504649920] |