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| n | a(n) |
|---|---|
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 3 |
| 6 | 1 |
| 7 | 1 |
| 8 | 32 |
| 9 | 693 |
| 10 | 7720 |
| 11 | 44150 |
| 12 | 138312 |
| 13 | 247380 |
| 14 | 252000 |
| 15 | 136080 |
| 16 | 30240 |
| 17 | 1 |
| 18 | 2134 |
| 19 | 4971504 |
| 20 | 1513872568 |
| 21 | 124978335900 |
| 22 | 4307090369304 |
| 23 | 78010256156784 |
| 24 | 849590196841344 |
| 25 | 6053725780061400 |
| 26 | 29824685516682000 |
| 27 | 105382759395846240 |
| 28 | 273441179492268480 |
[1,1,3,3,1,1,32,693,7720,44150,138312,247380, 252000,136080,30240,1,2134,4971504,1513872568, 124978335900,4307090369304,78010256156784, 849590196841344,6053725780061400, 29824685516682000,105382759395846240, 273441179492268480] |