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| n | a(n) |
|---|---|
| 1 | 28 |
| 2 | 117 |
| 3 | 444 |
| 4 | 1588 |
| 5 | 5387 |
| 6 | 17645 |
| 7 | 56425 |
| 8 | 177289 |
| 9 | 549976 |
| 10 | 1690006 |
| 11 | 5158577 |
| 12 | 15668130 |
| 13 | 47422454 |
| 14 | 143161949 |
| 15 | 431407408 |
| 16 | 1298283373 |
| 17 | 3903506520 |
| 18 | 11728583997 |
| 19 | 35224065039 |
| 20 | 105750970102 |
[28,117,444,1588,5387,17645,56425,177289,549976, 1690006,5158577,15668130,47422454,143161949, 431407408,1298283373,3903506520,11728583997, 35224065039,105750970102] |