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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 16 |
| 4 | 65 |
| 5 | 256 |
| 6 | 1024 |
| 7 | 4096 |
| 8 | 16388 |
| 9 | 65536 |
| 10 | 262144 |
| 11 | 1048576 |
| 12 | 4194320 |
| 13 | 16777216 |
| 14 | 67108864 |
| 15 | 268435456 |
| 16 | 1073741889 |
| 17 | 4294967296 |
| 18 | 17179869184 |
| 19 | 68719476736 |
| 20 | 274877907200 |
| 21 | 1099511627776 |
| 22 | 4398046511104 |
| 23 | 17592186044416 |
| 24 | 70368744178688 |
| 25 | 281474976710656 |
| 26 | 1125899906842624 |
[1,4,16,65,256,1024,4096,16388,65536,262144, 1048576,4194320,16777216,67108864,268435456, 1073741889,4294967296,17179869184,68719476736, 274877907200,1099511627776,4398046511104, 17592186044416,70368744178688,281474976710656, 1125899906842624] |