Separate the string using the shifted characters as delimiters:
@7 ^4 @5 * &29 @401 ^4 # ( % @ %12 ^4 #43 #6 ^4 @ * ( @16
Convert everything to numbers:
27 64 25 8 729 2401 64 3 9 5 2 512 64 343 36 64 2 8 9 216
Now that we have separated numbers we can see that every number has single digit factors of the same digit(ie 27=3x3x3). Unfortunately there are a few that are ambiguous groups based on this pattern (ie 8=8 or 8=2x2x2) and a controlled brute must be performed. Pre-brute string:
3x3x3 (2x2x2x2x2x2/4x4x4/8x8) 5x5 (2x2x2/8) 9x9x9 7x7x7x7 (2x2x2x2x2x2/4x4x4/8x8) 3 (3x3/9) 5 2 (2x2x2x2x2x2x2x2x2/8x8x8) (2x2x2x2x2x2/4x4x4/8x8) 7x7x7 6x6 (2x2x2x2x2x2/4x4x4/8x8) 2 (2x2x2/8) (3x3/9) 6x6x6
Certain ambiguities can be eliminated if the reference index is identified. In this case it is the phone keypad (3x3x3=3rd letter on the “3” button = F. 2x2x2x2x2x2 is not a valid grouping since there is no 6th letter on the “2” button.). String with only keypad possibilities:
3x3x3 (4x4x4/8x8) 5x5 (2x2x2/8) 9x9x9 7x7x7x7 (4x4x4/8x8) 3 (3x3/9) 5 2 (8x8x8) (4x4x4/8x8) 7x7x7 6x6 (4x4x4/8x8) 2 (2x2x2/8) (3x3/9) 6x6x6
Using our index, translate to letters:
F(I/U)K(C/T)YS(I/U)D(E/W)JAV(I/U)RN(I/U)A(C/T)(C/W)O
Although it is difficult to see there is the beginning of a passcode prefix that can be formed assuming the numbers are represented by the first two letters of the written number (FI=FIVE=5). Separating the prefix, keyword and suffix out helps to make it more evident:
F(I/U)K(C/T)YS(I/U) D(E/W)JAV(I/U) RN(I/U)A(C/T)(C/W)O
Certain letters can now be eliminated based on the limitations of the way the numbers are represented and after the keyword is identified:
FIK(C/T)YSI DEJAVU RNIATWO
After subbing in the numbers there are only 2 possibilities left and one is the correct passcode:
5KTY6DEJAVUR9A2O
