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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 11 |
| 3 | 37 |
| 4 | 138 |
| 5 | 427 |
| 6 | 1444 |
| 7 | 4903 |
| 8 | 16506 |
| 9 | 55852 |
| 10 | 187749 |
| 11 | 633539 |
| 12 | 2137749 |
| 13 | 7207808 |
| 14 | 24313464 |
| 15 | 81989501 |
| 16 | 276535047 |
| 17 | 932671520 |
| 18 | 3145519293 |
| 19 | 10608869096 |
| 20 | 35779805168 |
| 21 | 120673337749 |
| 22 | 406989614355 |
| 23 | 1372634462321 |
| 24 | 4629426356298 |
[3,11,37,138,427,1444,4903,16506,55852,187749, 633539,2137749,7207808,24313464,81989501, 276535047,932671520,3145519293,10608869096, 35779805168,120673337749,406989614355, 1372634462321,4629426356298] |