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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 10 |
| 4 | 47 |
| 5 | 246 |
| 6 | 882 |
| 7 | 3921 |
| 8 | 18223 |
| 9 | 84790 |
| 10 | 432518 |
| 11 | 1863951 |
| 12 | 8892842 |
| 13 | 42656147 |
| 14 | 204204353 |
| 15 | 1025014815 |
| 16 | 4728033983 |
| 17 | 22948258742 |
| 18 | 111605089014 |
| 19 | 541696830843 |
| 20 | 2708218059022 |
| 21 | 12861557284425 |
| 22 | 62938669549583 |
| 23 | 308273057334413 |
| 24 | 1508708926286914 |
| 25 | 7533652902408071 |
[1,1,3,10,47,246,882,3921,18223,84790,432518, 1863951,8892842,42656147,204204353,1025014815, 4728033983,22948258742,111605089014,541696830843, 2708218059022,12861557284425,62938669549583, 308273057334413,1508708926286914,7533652902408071] |