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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 0 |
| 4 | 2 |
| 5 | 4 |
| 6 | 9 |
| 7 | 18 |
| 8 | 36 |
| 9 | 60 |
| 10 | 105 |
| 11 | 210 |
| 12 | 324 |
| 13 | 648 |
| 14 | 1080 |
| 15 | 1680 |
| 16 | 2352 |
| 17 | 4704 |
| 18 | 6480 |
| 19 | 12960 |
| 20 | 18360 |
| 21 | 27200 |
| 22 | 43200 |
| 23 | 86400 |
| 24 | 110880 |
| 25 | 155232 |
| 26 | 243936 |
| 27 | 310464 |
| 28 | 423360 |
| 29 | 846720 |
| 30 | 1080000 |
| 31 | 2160000 |
| 32 | 2592000 |
| 33 | 3686400 |
| 34 | 5713920 |
| 35 | 7713792 |
| 36 | 9237888 |
| 37 | 18475776 |
[1,0,0,2,4,9,18,36,60,105,210,324,648,1080,1680, 2352,4704,6480,12960,18360,27200,43200,86400, 110880,155232,243936,310464,423360,846720,1080000, 2160000,2592000,3686400,5713920,7713792,9237888, 18475776] |