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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 2 |
| 2 | 5 |
| 3 | 13 |
| 4 | 29 |
| 5 | 61 |
| 6 | 125 |
| 7 | 253 |
| 8 | 509 |
| 9 | 1021 |
| 10 | 2045 |
| 11 | 4093 |
| 12 | 8189 |
| 13 | 16381 |
| 14 | 32765 |
| 15 | 65533 |
| 16 | 131069 |
| 17 | 262141 |
| 18 | 524285 |
| 19 | 1048573 |
| 20 | 2097149 |
| 21 | 4194301 |
| 22 | 8388605 |
| 23 | 16777213 |
| 24 | 33554429 |
| 25 | 67108861 |
| 26 | 134217725 |
| 27 | 268435453 |
| 28 | 536870909 |
| 29 | 1073741821 |
[0,2,5,13,29,61,125,253,509,1021,2045,4093,8189, 16381,32765,65533,131069,262141,524285,1048573, 2097149,4194301,8388605,16777213,33554429, 67108861,134217725,268435453,536870909,1073741821] |