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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 2 |
| 2 | 6 |
| 3 | 12 |
| 4 | 20 |
| 5 | 30 |
| 6 | 42 |
| 7 | 56 |
| 8 | 72 |
| 9 | 90 |
| 10 | 110 |
| 11 | 132 |
| 12 | 156 |
| 13 | 182 |
| 14 | 210 |
| 15 | 240 |
| 16 | 272 |
| 17 | 306 |
| 18 | 342 |
| 19 | 380 |
| 20 | 420 |
| 21 | 462 |
| 22 | 506 |
| 23 | 552 |
| 24 | 600 |
| 25 | 650 |
| 26 | 702 |
| 27 | 756 |
| 28 | 812 |
| 29 | 870 |
| 30 | 930 |
| 31 | 992 |
| 32 | 1056 |
| 33 | 1122 |
| 34 | 1190 |
| 35 | 1260 |
| 36 | 1332 |
| 37 | 1406 |
| 38 | 1482 |
| 39 | 1560 |
| 40 | 1640 |
| 41 | 1722 |
| 42 | 1806 |
| 43 | 1892 |
| 44 | 1980 |
| 45 | 2070 |
| 46 | 2162 |
| 47 | 2256 |
| 48 | 2352 |
| 49 | 2450 |
| 50 | 2550 |
[0,2,6,12,20,30,42,56,72,90,110,132,156,182,210, 240,272,306,342,380,420,462,506,552,600,650,702, 756,812,870,930,992,1056,1122,1190,1260,1332,1406, 1482,1560,1640,1722,1806,1892,1980,2070,2162,2256, 2352,2450,2550] |