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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 18 |
| 4 | 39 |
| 5 | 96 |
| 6 | 225 |
| 7 | 543 |
| 8 | 1293 |
| 9 | 3096 |
| 10 | 7392 |
| 11 | 17673 |
| 12 | 42228 |
| 13 | 100929 |
| 14 | 241197 |
| 15 | 576441 |
| 16 | 1377606 |
| 17 | 3292314 |
| 18 | 7868187 |
| 19 | 18803964 |
| 20 | 44939013 |
| 21 | 107398431 |
| 22 | 256668285 |
| 23 | 613403916 |
| 24 | 1465955712 |
| 25 | 3503443917 |
| 26 | 8372776200 |
| 27 | 20009848437 |
| 28 | 47820940581 |
| 29 | 114285841233 |
[1,6,18,39,96,225,543,1293,3096,7392,17673,42228, 100929,241197,576441,1377606,3292314,7868187, 18803964,44939013,107398431,256668285,613403916, 1465955712,3503443917,8372776200,20009848437, 47820940581,114285841233] |