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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 9 |
| 3 | 20 |
| 4 | 61 |
| 5 | 189 |
| 6 | 544 |
| 7 | 1629 |
| 8 | 4973 |
| 9 | 15040 |
| 10 | 45739 |
| 11 | 140129 |
| 12 | 429448 |
| 13 | 1318027 |
| 14 | 4054639 |
| 15 | 12485046 |
| 16 | 38469569 |
| 17 | 118629261 |
| 18 | 366006920 |
| 19 | 1129623099 |
| 20 | 3487480563 |
| 21 | 10769378230 |
| 22 | 33261326067 |
| 23 | 102741225843 |
| 24 | 317390237024 |
| 25 | 980560274021 |
| 26 | 3029559578685 |
[3,9,20,61,189,544,1629,4973,15040,45739,140129, 429448,1318027,4054639,12485046,38469569, 118629261,366006920,1129623099,3487480563, 10769378230,33261326067,102741225843,317390237024, 980560274021,3029559578685] |