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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 2 |
| 3 | 0 |
| 4 | 6 |
| 5 | 4 |
| 6 | 12 |
| 7 | 12 |
| 8 | 30 |
| 9 | 36 |
| 10 | 60 |
| 11 | 80 |
| 12 | 132 |
| 13 | 180 |
| 14 | 264 |
| 15 | 360 |
| 16 | 522 |
| 17 | 712 |
| 18 | 990 |
| 19 | 1344 |
| 20 | 1844 |
| 21 | 2472 |
| 22 | 3324 |
| 23 | 4420 |
| 24 | 5892 |
| 25 | 7764 |
| 26 | 10212 |
| 27 | 13344 |
| 28 | 17400 |
| 29 | 22556 |
| 30 | 29160 |
| 31 | 37524 |
| 32 | 48166 |
| 33 | 61560 |
| 34 | 78456 |
| 35 | 99648 |
| 36 | 126234 |
| 37 | 159396 |
| 38 | 200740 |
| 39 | 252096 |
| 40 | 315828 |
[0,2,0,6,4,12,12,30,36,60,80,132,180,264,360,522, 712,990,1344,1844,2472,3324,4420,5892,7764,10212, 13344,17400,22556,29160,37524,48166,61560,78456, 99648,126234,159396,200740,252096,315828] |