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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 9 |
| 3 | 35 |
| 4 | 105 |
| 5 | 279 |
| 6 | 693 |
| 7 | 1651 |
| 8 | 3825 |
| 9 | 8687 |
| 10 | 19437 |
| 11 | 42987 |
| 12 | 94185 |
| 13 | 204775 |
| 14 | 442341 |
| 15 | 950243 |
| 16 | 2031585 |
| 17 | 4325343 |
| 18 | 9175005 |
| 19 | 19398619 |
| 20 | 40894425 |
| 21 | 85983191 |
| 22 | 180355029 |
| 23 | 377487315 |
| 24 | 788529105 |
| 25 | 1644167119 |
| 26 | 3422552013 |
| 27 | 7113539531 |
| 28 | 14763950025 |
| 29 | 30601641927 |
| 30 | 63350767557 |
| 31 | 130996502467 |
| 32 | 270582939585 |
[1,9,35,105,279,693,1651,3825,8687,19437,42987, 94185,204775,442341,950243,2031585,4325343, 9175005,19398619,40894425,85983191,180355029, 377487315,788529105,1644167119,3422552013, 7113539531,14763950025,30601641927,63350767557, 130996502467,270582939585] |