## On the Subject of Perspective Pegs

Everything is different from the perspective of another.

### Step 1: Key Colour

• Calculate the alphabetic position difference of the first two letters in the serial number. (A = 1, B = 2, etc.)
• Regard the difference between alphabetic positions to be positive.
• If there are four or more letters in the serial number, add the position difference of the third and fourth letters.
• Look up this number on the Key Colour table to obtain a colour.

### Step 2: Sequence Permutation

• Starting from the peg with three or more sides in this colour and proceeding clockwise, read the outermost facing colour of each peg to form a colour sequence of length five; this is the current sequence.
• Determine which column of the Sequence Permutation table to use.
• For each entry in the relevant column:
• If the prime sequence is present in the current sequence, replace the first occurrence with the alternate sequence to form the new current sequence.
• Otherwise, if the reverse of the prime sequence is present, replace the last occurrence with the reverse of the alternate sequence.
• Finally, take the first three colours in the current sequence to obtain the key sequence.

### Step 3: Key Sequence

• Angle the bomb with one peg close to you and in the centre of your view, then observe the five colours facing you in a line; this is the candidate sequence for this view.
• The key sequence is present in one of the five candidate sequences exactly once, either forward or reverse.
• Locate the candidate sequence that contains the key sequence, and press the three pegs representing the key sequence in order.
• If the key sequence is the same backwards as it is forwards, you can press the three pegs in either forward or reverse order.

#### Table 1.1 Key Colour

Regard the difference between alphabetic positions to be positive.

Take the least significant digit of the number, and look up in the table:

 0 3 Red 5 8 Blue 4 9 Yellow 2 6 Purple 1 7 Green

#### Table 1.2 Sequence Permutation

R – Red, Y – Yellow, G – Green, B – Blue, P – Purple

Determine which column to use based on battery count.

Perform permutations from top to bottom:

 1 – 2 Batteries 3 – 4 Batteries 0, 5+ Batteries Prime Alternate Prime Alternate Prime Alternate R Y Y B P Y B P B Y B G P Y B R G B Y P G P B R Y Y P B R P Y R P R Y R R G P B G R G R B Y P B G Y R G B P Y B G B Y Y R P Y G B G B Y G P G R P P R R Y P Y G G P B R R P Y G Y B B G B P Y G G P B Y G Y P P G P B R Y G B G P Y P R P B B G R Y Y B B R P G G G Y R R Y R R P B Y G P P Y Y