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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 12 |
| 5 | 29 |
| 6 | 93 |
| 7 | 266 |
| 8 | 889 |
| 9 | 2819 |
| 10 | 9704 |
| 11 | 32547 |
| 12 | 114559 |
| 13 | 402548 |
| 14 | 1447243 |
| 15 | 5232685 |
| 16 | 19135813 |
| 17 | 70627631 |
| 18 | 263062730 |
| 19 | 986459954 |
| 20 | 3723667384 |
| 21 | 14131582708 |
| 22 | 54009336165 |
| 23 | 207318335930 |
| 24 | 800149593714 |
| 25 | 3098358305471 |
| 26 | 12056855792087 |
| 27 | 47090041195574 |
| 28 | 184619039183558 |
| 29 | 726005646404804 |
| 30 | 2863646013210247 |
[1,1,2,4,12,29,93,266,889,2819,9704,32547,114559, 402548,1447243,5232685,19135813,70627631, 263062730,986459954,3723667384,14131582708, 54009336165,207318335930,800149593714, 3098358305471,12056855792087,47090041195574, 184619039183558,726005646404804,2863646013210247] |