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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 40 |
| 3 | 200 |
| 4 | 760 |
| 5 | 2280 |
| 6 | 5640 |
| 7 | 12120 |
| 8 | 23800 |
| 9 | 43040 |
| 10 | 73840 |
| 11 | 120240 |
| 12 | 188040 |
| 13 | 283680 |
| 14 | 415840 |
| 15 | 593240 |
| 16 | 827680 |
| 17 | 1131240 |
| 18 | 1519200 |
| 19 | 2007240 |
| 20 | 2614720 |
| 21 | 3361280 |
| 22 | 4271080 |
| 23 | 5368320 |
| 24 | 6681840 |
| 25 | 8241120 |
| 26 | 10080760 |
| 27 | 12235400 |
| 28 | 14745640 |
| 29 | 17652360 |
| 30 | 21002520 |
[0,40,200,760,2280,5640,12120,23800,43040,73840, 120240,188040,283680,415840,593240,827680,1131240, 1519200,2007240,2614720,3361280,4271080,5368320, 6681840,8241120,10080760,12235400,14745640, 17652360,21002520] |