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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 6 |
| 3 | 36 |
| 4 | 30 |
| 5 | 120 |
| 6 | 300 |
| 7 | 3600 |
| 8 | 15000 |
| 9 | 210 |
| 10 | 672 |
| 11 | 1260 |
| 12 | 42000 |
| 13 | 2940 |
| 14 | 28224 |
| 15 | 88200 |
| 16 | 164640 |
| 17 | 288120 |
| 18 | 4609920 |
| 19 | 216090000 |
| 20 | 21176820 |
| 21 | 564715200 |
| 22 | 2310 |
| 23 | 11880 |
| 24 | 18480 |
| 25 | 4435200 |
| 26 | 19404000 |
| 27 | 66555720 |
| 28 | 44370480000 |
| 29 | 50820 |
| 30 | 1306800 |
| 31 | 2845920 |
| 32 | 63748608 |
| 33 | 5856903360 |
| 34 | 328703760 |
| 35 | 306790176000 |
| 36 | 12298440 |
| 37 | 7906140000 |
| 38 | 645668100 |
| 39 | 33746919360 |
| 40 | 15874550866944 |
[2,6,36,30,120,300,3600,15000,210,672,1260,42000, 2940,28224,88200,164640,288120,4609920,216090000, 21176820,564715200,2310,11880,18480,4435200, 19404000,66555720,44370480000,50820,1306800, 2845920,63748608,5856903360,328703760, 306790176000,12298440,7906140000,645668100, 33746919360,15874550866944] |