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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 6 |
| 2 | 27 |
| 3 | 101 |
| 4 | 346 |
| 5 | 1131 |
| 6 | 3611 |
| 7 | 11396 |
| 8 | 35761 |
| 9 | 111906 |
| 10 | 349700 |
| 11 | 1092039 |
| 12 | 3409031 |
| 13 | 10640179 |
| 14 | 33206991 |
| 15 | 103631414 |
| 16 | 323402952 |
| 17 | 1009233980 |
| 18 | 3149469548 |
| 19 | 9828376731 |
| 20 | 30670834516 |
| 21 | 95712596642 |
| 22 | 298684343689 |
| 23 | 932085486213 |
| 24 | 2908700435744 |
[1,6,27,101,346,1131,3611,11396,35761,111906, 349700,1092039,3409031,10640179,33206991, 103631414,323402952,1009233980,3149469548, 9828376731,30670834516,95712596642,298684343689, 932085486213,2908700435744] |