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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 11 |
| 4 | 47 |
| 5 | 155 |
| 6 | 567 |
| 7 | 2221 |
| 8 | 8173 |
| 9 | 32497 |
| 10 | 128021 |
| 11 | 500621 |
| 12 | 2045881 |
| 13 | 8159033 |
| 14 | 33233365 |
| 15 | 136610895 |
| 16 | 556058415 |
| 17 | 2309390411 |
| 18 | 9545735783 |
| 19 | 39570216519 |
| 20 | 165775628203 |
| 21 | 690570644667 |
| 22 | 2900036643435 |
| 23 | 12206706417779 |
| 24 | 51300646746555 |
| 25 | 217150025395355 |
| 26 | 917877590444083 |
| 27 | 3888524712012907 |
[1,1,5,11,47,155,567,2221,8173,32497,128021, 500621,2045881,8159033,33233365,136610895, 556058415,2309390411,9545735783,39570216519, 165775628203,690570644667,2900036643435, 12206706417779,51300646746555,217150025395355, 917877590444083,3888524712012907] |