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| n | a(n) |
|---|---|
| 1 | 20 |
| 2 | 30 |
| 3 | 156 |
| 4 | 600 |
| 5 | 420 |
| 6 | 1640 |
| 7 | 3660 |
| 8 | 520 |
| 9 | 2590 |
| 10 | 7140 |
| 11 | 1224 |
| 12 | 10920 |
| 13 | 8190 |
| 14 | 20880 |
| 15 | 32580 |
| 16 | 4872 |
| 17 | 19998 |
| 18 | 5220 |
| 19 | 48620 |
| 20 | 69960 |
| 21 | 3150 |
| 22 | 41470 |
| 23 | 97656 |
| 24 | 132860 |
| 25 | 19080 |
| 26 | 76830 |
| 27 | 176820 |
| 28 | 230880 |
| 29 | 131070 |
| 30 | 12740 |
| 31 | 296480 |
| 32 | 11100 |
| 33 | 375156 |
| 34 | 52360 |
| 35 | 209950 |
| 36 | 468540 |
| 37 | 64080 |
[20,30,156,600,420,1640,3660,520,2590,7140,1224, 10920,8190,20880,32580,4872,19998,5220,48620, 69960,3150,41470,97656,132860,19080,76830,176820, 230880,131070,12740,296480,11100,375156,52360, 209950,468540,64080] |