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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 6 |
| 3 | 21 |
| 4 | 85 |
| 5 | 342 |
| 6 | 1365 |
| 7 | 5461 |
| 8 | 21846 |
| 9 | 87381 |
| 10 | 349525 |
| 11 | 1398102 |
| 12 | 5592405 |
| 13 | 22369621 |
| 14 | 89478486 |
| 15 | 357913941 |
| 16 | 1431655765 |
| 17 | 5726623062 |
| 18 | 22906492245 |
| 19 | 91625968981 |
| 20 | 366503875926 |
| 21 | 1466015503701 |
| 22 | 5864062014805 |
| 23 | 23456248059222 |
| 24 | 93824992236885 |
| 25 | 375299968947541 |
[0,1,6,21,85,342,1365,5461,21846,87381,349525, 1398102,5592405,22369621,89478486,357913941, 1431655765,5726623062,22906492245,91625968981, 366503875926,1466015503701,5864062014805, 23456248059222,93824992236885,375299968947541] |