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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 15 |
| 4 | 46 |
| 5 | 128 |
| 6 | 384 |
| 7 | 1114 |
| 8 | 3332 |
| 9 | 9903 |
| 10 | 29671 |
| 11 | 88721 |
| 12 | 266151 |
| 13 | 797593 |
| 14 | 2392649 |
| 15 | 7175709 |
| 16 | 21526834 |
| 17 | 64573556 |
| 18 | 193720536 |
| 19 | 581141026 |
| 20 | 1743422288 |
| 21 | 5230207428 |
| 22 | 15690619684 |
| 23 | 47071679294 |
| 24 | 141215037738 |
| 25 | 423644574301 |
| 26 | 1270933715189 |
| 27 | 3812799550089 |
| 28 | 11438398630159 |
[1,5,15,46,128,384,1114,3332,9903,29671,88721, 266151,797593,2392649,7175709,21526834,64573556, 193720536,581141026,1743422288,5230207428, 15690619684,47071679294,141215037738,423644574301, 1270933715189,3812799550089,11438398630159] |