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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 4 |
| 3 | 7 |
| 4 | 18 |
| 5 | 35 |
| 6 | 74 |
| 7 | 147 |
| 8 | 298 |
| 9 | 595 |
| 10 | 1194 |
| 11 | 2387 |
| 12 | 4778 |
| 13 | 9555 |
| 14 | 19114 |
| 15 | 38227 |
| 16 | 76458 |
| 17 | 152915 |
| 18 | 305834 |
| 19 | 611667 |
| 20 | 1223338 |
| 21 | 2446675 |
| 22 | 4893354 |
| 23 | 9786707 |
| 24 | 19573418 |
| 25 | 39146835 |
| 26 | 78293674 |
| 27 | 156587347 |
| 28 | 313174698 |
| 29 | 626349395 |
| 30 | 1252698794 |
| 31 | 2505397587 |
| 32 | 5010795178 |
| 33 | 10021590355 |
| 34 | 20043180714 |
[0,4,7,18,35,74,147,298,595,1194,2387,4778,9555, 19114,38227,76458,152915,305834,611667,1223338, 2446675,4893354,9786707,19573418,39146835, 78293674,156587347,313174698,626349395,1252698794, 2505397587,5010795178,10021590355,20043180714] |