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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 9 |
| 4 | 20 |
| 5 | 43 |
| 6 | 90 |
| 7 | 185 |
| 8 | 376 |
| 9 | 759 |
| 10 | 1526 |
| 11 | 3061 |
| 12 | 6132 |
| 13 | 12275 |
| 14 | 24562 |
| 15 | 49137 |
| 16 | 98288 |
| 17 | 196591 |
| 18 | 393198 |
| 19 | 786413 |
| 20 | 1572844 |
| 21 | 3145707 |
| 22 | 6291434 |
| 23 | 12582889 |
| 24 | 25165800 |
| 25 | 50331623 |
| 26 | 100663270 |
| 27 | 201326565 |
| 28 | 402653156 |
| 29 | 805306339 |
| 30 | 1610612706 |
| 31 | 3221225441 |
| 32 | 6442450912 |
| 33 | 12884901855 |
| 34 | 25769803742 |
| 35 | 51539607517 |
[1,4,9,20,43,90,185,376,759,1526,3061,6132,12275, 24562,49137,98288,196591,393198,786413,1572844, 3145707,6291434,12582889,25165800,50331623, 100663270,201326565,402653156,805306339, 1610612706,3221225441,6442450912,12884901855, 25769803742,51539607517] |