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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 11 |
| 5 | 43 |
| 6 | 183 |
| 7 | 813 |
| 8 | 3731 |
| 9 | 17563 |
| 10 | 84303 |
| 11 | 411093 |
| 12 | 2030833 |
| 13 | 10141953 |
| 14 | 51117801 |
| 15 | 259695379 |
| 16 | 1328454221 |
| 17 | 6836777765 |
| 18 | 35373248213 |
| 19 | 183892104895 |
| 20 | 960066929119 |
| 21 | 5031617143079 |
| 22 | 26462109374051 |
| 23 | 139609962072913 |
| 24 | 738695107457919 |
[1,1,3,11,43,183,813,3731,17563,84303,411093, 2030833,10141953,51117801,259695379,1328454221, 6836777765,35373248213,183892104895,960066929119, 5031617143079,26462109374051,139609962072913, 738695107457919] |