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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 16 |
| 4 | 74 |
| 5 | 256 |
| 6 | 1088 |
| 7 | 4096 |
| 8 | 16660 |
| 9 | 65672 |
| 10 | 263168 |
| 11 | 1048576 |
| 12 | 4199584 |
| 13 | 16777216 |
| 14 | 67125248 |
| 15 | 268439552 |
| 16 | 1073810115 |
| 17 | 4294967296 |
| 18 | 17180148256 |
| 19 | 68719476736 |
| 20 | 274878974464 |
| 21 | 1099511693312 |
| 22 | 4398050705408 |
| 23 | 17592186044416 |
| 24 | 70368761297216 |
| 25 | 281474976743552 |
| 26 | 1125899973951488 |
| 27 | 4503599628419888 |
[1,4,16,74,256,1088,4096,16660,65672,263168, 1048576,4199584,16777216,67125248,268439552, 1073810115,4294967296,17180148256,68719476736, 274878974464,1099511693312,4398050705408, 17592186044416,70368761297216,281474976743552, 1125899973951488,4503599628419888] |