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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 3 |
| 3 | 5 |
| 4 | 7 |
| 5 | 22 |
| 6 | 39 |
| 7 | 85 |
| 8 | 133 |
| 9 | 506 |
| 10 | 1131 |
| 11 | 2635 |
| 12 | 4921 |
| 13 | 20746 |
| 14 | 48633 |
| 15 | 123845 |
| 16 | 260813 |
| 17 | 1224014 |
| 18 | 2966613 |
| 19 | 8297615 |
| 20 | 18517723 |
| 21 | 89353022 |
| 22 | 234362427 |
| 23 | 688702045 |
| 24 | 1648077347 |
| 25 | 8667243134 |
| 26 | 23670605127 |
| 27 | 70936310635 |
| 28 | 176344276129 |
[1,2,3,5,7,22,39,85,133,506,1131,2635,4921,20746, 48633,123845,260813,1224014,2966613,8297615, 18517723,89353022,234362427,688702045,1648077347, 8667243134,23670605127,70936310635,176344276129] |