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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 12 |
| 4 | 48 |
| 5 | 240 |
| 6 | 240 |
| 7 | 1680 |
| 8 | 3360 |
| 9 | 30240 |
| 10 | 30240 |
| 11 | 332640 |
| 12 | 332640 |
| 13 | 4324320 |
| 14 | 4324320 |
| 15 | 4324320 |
| 16 | 1081080 |
| 17 | 18378360 |
| 18 | 6126120 |
| 19 | 116396280 |
| 20 | 14549535 |
| 21 | 4157010 |
| 22 | 16628040 |
| 23 | 382444920 |
| 24 | 3059559360 |
| 25 | 15297796800 |
| 26 | 15297796800 |
| 27 | 45893390400 |
| 28 | 321253732800 |
| 29 | 9316358251200 |
| 30 | 9316358251200 |
| 31 | 288807105787200 |
| 32 | 144403552893600 |
[1,4,12,48,240,240,1680,3360,30240,30240,332640, 332640,4324320,4324320,4324320,1081080,18378360, 6126120,116396280,14549535,4157010,16628040, 382444920,3059559360,15297796800,15297796800, 45893390400,321253732800,9316358251200, 9316358251200,288807105787200,144403552893600] |