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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 9 |
| 3 | 33 |
| 4 | 135 |
| 5 | 591 |
| 6 | 2709 |
| 7 | 12837 |
| 8 | 62379 |
| 9 | 309147 |
| 10 | 1556577 |
| 11 | 7940169 |
| 12 | 40946607 |
| 13 | 213118119 |
| 14 | 1118080557 |
| 15 | 5906404557 |
| 16 | 31390735059 |
| 17 | 167727039027 |
| 18 | 900478280889 |
| 19 | 4855086475761 |
| 20 | 26277928981335 |
| 21 | 142724482802943 |
| 22 | 777647813128389 |
| 23 | 4249385026394613 |
| 24 | 23282201473312635 |
| 25 | 127874913883456971 |
| 26 | 703929221807756049 |
[1,3,9,33,135,591,2709,12837,62379,309147,1556577, 7940169,40946607,213118119,1118080557,5906404557, 31390735059,167727039027,900478280889, 4855086475761,26277928981335,142724482802943, 777647813128389,4249385026394613, 23282201473312635,127874913883456971, 703929221807756049] |