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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 7 |
| 2 | 27 |
| 3 | 83 |
| 4 | 227 |
| 5 | 579 |
| 6 | 1411 |
| 7 | 3331 |
| 8 | 7683 |
| 9 | 17411 |
| 10 | 38915 |
| 11 | 86019 |
| 12 | 188419 |
| 13 | 409603 |
| 14 | 884739 |
| 15 | 1900547 |
| 16 | 4063235 |
| 17 | 8650755 |
| 18 | 18350083 |
| 19 | 38797315 |
| 20 | 81788931 |
| 21 | 171966467 |
| 22 | 360710147 |
| 23 | 754974723 |
| 24 | 1577058307 |
| 25 | 3288334339 |
| 26 | 6845104131 |
| 27 | 14227079171 |
| 28 | 29527900163 |
| 29 | 61203283971 |
[1,7,27,83,227,579,1411,3331,7683,17411,38915, 86019,188419,409603,884739,1900547,4063235, 8650755,18350083,38797315,81788931,171966467, 360710147,754974723,1577058307,3288334339, 6845104131,14227079171,29527900163,61203283971] |