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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 6 |
| 3 | 12 |
| 4 | 18 |
| 5 | 28 |
| 6 | 36 |
| 7 | 66 |
| 8 | 246 |
| 9 | 268 |
| 10 | 396 |
| 11 | 1476 |
| 12 | 1876 |
| 13 | 2044 |
| 14 | 2556 |
| 15 | 2706 |
| 16 | 3556 |
| 17 | 5986 |
| 18 | 9514 |
| 19 | 11034 |
| 20 | 16236 |
| 21 | 17466 |
| 22 | 25626 |
| 23 | 31956 |
| 24 | 34716 |
| 25 | 120786 |
| 26 | 149076 |
| 27 | 153756 |
| 28 | 246484 |
| 29 | 259588 |
| 30 | 281886 |
| 31 | 283276 |
| 32 | 483636 |
| 33 | 552926 |
| 34 | 559966 |
| 35 | 623566 |
| 36 | 670186 |
| 37 | 721846 |
| 38 | 846076 |
| 39 | 1050666 |
[4,6,12,18,28,36,66,246,268,396,1476,1876,2044, 2556,2706,3556,5986,9514,11034,16236,17466,25626, 31956,34716,120786,149076,153756,246484,259588, 281886,283276,483636,552926,559966,623566,670186, 721846,846076,1050666] |