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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 20 |
| 3 | 40 |
| 4 | 60 |
| 5 | 70 |
| 6 | 180 |
| 7 | 330 |
| 8 | 540 |
| 9 | 1155 |
| 10 | 1581 |
| 11 | 2805 |
| 12 | 2856 |
| 13 | 3876 |
| 14 | 5544 |
| 15 | 16830 |
| 16 | 27060 |
| 17 | 62244 |
| 18 | 82680 |
| 19 | 90090 |
| 20 | 175440 |
| 21 | 237456 |
| 22 | 249424 |
| 23 | 273819 |
| 24 | 413820 |
| 25 | 431548 |
| 26 | 534660 |
| 27 | 860706 |
| 28 | 1074744 |
| 29 | 1205750 |
| 30 | 1306620 |
| 31 | 1630200 |
| 32 | 1764070 |
| 33 | 1962820 |
| 34 | 1983150 |
[6,20,40,60,70,180,330,540,1155,1581,2805,2856, 3876,5544,16830,27060,62244,82680,90090,175440, 237456,249424,273819,413820,431548,534660,860706, 1074744,1205750,1306620,1630200,1764070,1962820, 1983150] |