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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 10 |
| 3 | 29 |
| 4 | 88 |
| 5 | 259 |
| 6 | 771 |
| 7 | 2284 |
| 8 | 6786 |
| 9 | 20191 |
| 10 | 60189 |
| 11 | 179654 |
| 12 | 536925 |
| 13 | 1606221 |
| 14 | 4808601 |
| 15 | 14403804 |
| 16 | 43163793 |
| 17 | 129388755 |
| 18 | 387946445 |
| 19 | 1163370778 |
| 20 | 3489117566 |
| 21 | 10465248174 |
| 22 | 31391306504 |
| 23 | 94164586011 |
| 24 | 282474177151 |
| 25 | 847381544167 |
| 26 | 2542059008323 |
| 27 | 7625998475474 |
| 28 | 22877623720244 |
[1,3,10,29,88,259,771,2284,6786,20191,60189, 179654,536925,1606221,4808601,14403804,43163793, 129388755,387946445,1163370778,3489117566, 10465248174,31391306504,94164586011,282474177151, 847381544167,2542059008323,7625998475474, 22877623720244] |