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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 21 |
| 5 | 67 |
| 6 | 195 |
| 7 | 653 |
| 8 | 2099 |
| 9 | 6933 |
| 10 | 23423 |
| 11 | 78535 |
| 12 | 271285 |
| 13 | 925973 |
| 14 | 3206663 |
| 15 | 11185071 |
| 16 | 38983433 |
| 17 | 137051515 |
| 18 | 482479299 |
| 19 | 1708206559 |
| 20 | 6052735529 |
| 21 | 21521991943 |
| 22 | 76778794491 |
| 23 | 274300787629 |
| 24 | 982476049335 |
| 25 | 3525512594021 |
| 26 | 12682333972857 |
| 27 | 45657403910329 |
| 28 | 164716081204213 |
| 29 | 595171088189807 |
| 30 | 2153100164896935 |
[1,1,3,7,21,67,195,653,2099,6933,23423,78535, 271285,925973,3206663,11185071,38983433,137051515, 482479299,1708206559,6052735529,21521991943, 76778794491,274300787629,982476049335, 3525512594021,12682333972857,45657403910329, 164716081204213,595171088189807,2153100164896935] |