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| n | a(n) |
|---|---|
| 0 | 6 |
| 1 | 1 |
| 2 | 9 |
| 3 | 28 |
| 4 | 77 |
| 5 | 231 |
| 6 | 702 |
| 7 | 2059 |
| 8 | 6157 |
| 9 | 18316 |
| 10 | 54489 |
| 11 | 162185 |
| 12 | 482678 |
| 13 | 1436397 |
| 14 | 4274853 |
| 15 | 12722028 |
| 16 | 37861085 |
| 17 | 112675763 |
| 18 | 335326230 |
| 19 | 997940307 |
| 20 | 2969899037 |
| 21 | 8838503884 |
| 22 | 26303639349 |
| 23 | 78280380217 |
| 24 | 232964641030 |
| 25 | 693309407681 |
[6,1,9,28,77,231,702,2059,6157,18316,54489,162185, 482678,1436397,4274853,12722028,37861085, 112675763,335326230,997940307,2969899037, 8838503884,26303639349,78280380217,232964641030, 693309407681] |