The Fibonacci sequence (often wrongly named the Fibonacci series) is the sequence 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, ... where after the first two entries, each number is the sum of the two previous numbers. Many, many papers have been written about the Fibonacci sequence and its occurrences, particularly in nature. One such occurrence is in the centre of the sunflower. Try counting the number of left-handed and right-handed spirals emanating from the centre. Amazing!
