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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 5 |
| 3 | 15 |
| 4 | 37 |
| 5 | 87 |
| 6 | 205 |
| 7 | 495 |
| 8 | 1173 |
| 9 | 2759 |
| 10 | 6493 |
| 11 | 15263 |
| 12 | 35749 |
| 13 | 83575 |
| 14 | 195181 |
| 15 | 455247 |
| 16 | 1060533 |
| 17 | 2468391 |
| 18 | 5740925 |
| 19 | 13342975 |
| 20 | 30993349 |
| 21 | 71956951 |
| 22 | 166991501 |
| 23 | 387397551 |
| 24 | 898427605 |
| 25 | 2083016071 |
| 26 | 4828379549 |
| 27 | 11189823071 |
| 28 | 25928070117 |
| 29 | 60069313847 |
| 30 | 139148806829 |
[1,3,5,15,37,87,205,495,1173,2759,6493,15263, 35749,83575,195181,455247,1060533,2468391,5740925, 13342975,30993349,71956951,166991501,387397551, 898427605,2083016071,4828379549,11189823071, 25928070117,60069313847,139148806829] |