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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 10 |
| 4 | 23 |
| 5 | 47 |
| 6 | 87 |
| 7 | 171 |
| 8 | 381 |
| 9 | 766 |
| 10 | 1407 |
| 11 | 2751 |
| 12 | 6111 |
| 13 | 12287 |
| 14 | 22527 |
| 15 | 44031 |
| 16 | 97791 |
| 17 | 196607 |
| 18 | 360447 |
| 19 | 704511 |
| 20 | 1564671 |
| 21 | 3145727 |
| 22 | 5767167 |
| 23 | 11272191 |
| 24 | 25034751 |
| 25 | 50331647 |
| 26 | 92274687 |
| 27 | 180355071 |
| 28 | 400556031 |
| 29 | 805306367 |
| 30 | 1476395007 |
| 31 | 2885681151 |
| 32 | 6408896511 |
| 33 | 12884901887 |
[1,2,5,10,23,47,87,171,381,766,1407,2751,6111, 12287,22527,44031,97791,196607,360447,704511, 1564671,3145727,5767167,11272191,25034751, 50331647,92274687,180355071,400556031,805306367, 1476395007,2885681151,6408896511,12884901887] |