Activities
confronted with the question of how many ways a staircase with 13 steps can be climbed if only steps of 1 and 2 are possible. (Such step patterns are used to access the lock of the Fibonacci secret society) [...] things, that this number is just the sum of the possibilities of climbing a staircase with 11 steps or 12 steps. The resulting numbers correspond to the Fibonacci numbers (1, 1, 2, 3, 5, 8, 13, 21, ...).
