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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 10 |
| 3 | 11 |
| 4 | 28 |
| 5 | 80 |
| 6 | 245 |
| 7 | 729 |
| 8 | 2604 |
| 9 | 8579 |
| 10 | 27943 |
| 11 | 95535 |
| 12 | 322511 |
| 13 | 1083870 |
| 14 | 3675083 |
| 15 | 12455625 |
| 16 | 42129388 |
| 17 | 142706185 |
| 18 | 483725646 |
| 19 | 1638434358 |
| 20 | 5551260311 |
| 21 | 18812259092 |
| 22 | 63741708473 |
| 23 | 215983981369 |
| 24 | 731885089125 |
| 25 | 2480017406380 |
| 26 | 8403581958869 |
[1,10,11,28,80,245,729,2604,8579,27943,95535, 322511,1083870,3675083,12455625,42129388, 142706185,483725646,1638434358,5551260311, 18812259092,63741708473,215983981369,731885089125, 2480017406380,8403581958869] |