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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 15 |
| 3 | 448 |
| 4 | 1023 |
| 5 | 2160 |
| 6 | 4218 |
| 7 | 4256 |
| 8 | 22528 |
| 9 | 65535 |
| 10 | 73216 |
| 11 | 602547 |
| 12 | 1048575 |
| 13 | 1432640 |
| 14 | 4194303 |
| 15 | 8567136 |
| 16 | 19299763 |
| 17 | 25165821 |
| 18 | 34713728 |
| 19 | 46467543 |
| 20 | 78913536 |
| 21 | 89522176 |
| 22 | 115343360 |
| 23 | 155493536 |
| 24 | 158414464 |
| 25 | 268435455 |
[1,15,448,1023,2160,4218,4256,22528,65535,73216, 602547,1048575,1432640,4194303,8567136,19299763, 25165821,34713728,46467543,78913536,89522176, 115343360,155493536,158414464,268435455] |