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Consider the spiral with polar equation r = va0 where a is constant. This spiral occurs frequently in flowers because it allows seeds to be arranged in the most efficient way possible. This highly structured natural phenonomen contains many mathematical ideas, including the Fibonacci sequence 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, . ... Sunflower Fibonacci of Pisa 1170 - 1250 AD The position of the n 'th seed on a sunflower is given in polar coordinates r = \\2Tyn, 0 = 2TynThe position of the n 'th seed on a sunflower is given in polar coordinates r = '/27r