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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 36 |
| 3 | 78 |
| 4 | 169 |
| 5 | 611 |
| 6 | 2209 |
| 7 | 6016 |
| 8 | 16384 |
| 9 | 51840 |
| 10 | 164025 |
| 11 | 478305 |
| 12 | 1394761 |
| 13 | 4249238 |
| 14 | 12945604 |
| 15 | 38516590 |
| 16 | 114597025 |
| 17 | 345332595 |
| 18 | 1040643081 |
| 19 | 3114412896 |
| 20 | 9320743936 |
| 21 | 27998628896 |
| 22 | 84105220081 |
| 23 | 252138754753 |
| 24 | 755885919889 |
| 25 | 2268515874246 |
[6,36,78,169,611,2209,6016,16384,51840,164025, 478305,1394761,4249238,12945604,38516590, 114597025,345332595,1040643081,3114412896, 9320743936,27998628896,84105220081,252138754753, 755885919889,2268515874246] |