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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 26 |
| 5 | 94 |
| 6 | 303 |
| 7 | 1154 |
| 8 | 4372 |
| 9 | 15884 |
| 10 | 62623 |
| 11 | 244797 |
| 12 | 953760 |
| 13 | 3813186 |
| 14 | 15279908 |
| 15 | 61791682 |
| 16 | 250255955 |
| 17 | 1021461121 |
| 18 | 4211124573 |
| 19 | 17290514080 |
| 20 | 71510272399 |
| 21 | 298032145342 |
| 22 | 1239217133213 |
| 23 | 5174916533646 |
| 24 | 21726875233801 |
| 25 | 91258664336181 |
| 26 | 384002548160385 |
| 27 | 1621744022534430 |
| 28 | 6863111651068515 |
[1,1,3,8,26,94,303,1154,4372,15884,62623,244797, 953760,3813186,15279908,61791682,250255955, 1021461121,4211124573,17290514080,71510272399, 298032145342,1239217133213,5174916533646, 21726875233801,91258664336181,384002548160385, 1621744022534430,6863111651068515] |