Doors 2013 level 115, is about arithmetic sequence, you have to guess the numbers behind the letters X and Z. the clue is the sum of the three rabbits on the floor
this is the solution
total the 3 numbers before the next number, for example
3 is the sum of 1 + 1 + 1
5 is the sum of 1 + 1 + 3
9 is the sum of 1 + 3 + 5
17 is the sum of 3 + 5 + 9
so X = 5 + 9 + 17 = 31
Z = 31 + 57 + 105 = 193
because at the top of keypad are listed XZ, so the answer is: 31193
press that number to open the door
