1, 1, 2, 3, 5, 8, 13, 2 1 ... Starting from the third number, each number is equal to the sum of the first two numbers. This strange sequence was put forward by Italian mathematician Fibonacci from the problem of rabbit reproduction. In memory of him, people call this series Fibonacci series, also known as rabbit series. Fibonacci found that rabbits breed very fast. After a few months, 1 became dozens of rabbits. Each pair of adult rabbits can give birth to 1 pair of rabbits every month. Rabbits can reproduce one month later and give birth to the first pair of rabbits two months later. In this way, 1 has 1 pairs of rabbits in early February, 1 pairs of rabbits in early March, 2 pairs of rabbits in April, 1 pairs of rabbits in June, 1 pairs of rabbits in March and 2 pairs of rabbits in May. In this way, 1-June, the logarithm of rabbits is 1,1,2, 3, 5, 8. Starting from the third number, each number is the sum of the first two numbers, and this is still the case. In addition, people have found this series from many places. Such as: jasmine (3 petals), buttercup (5 petals), delphinium (8 petals), marigold (13 petals), purple mussel (2 1 petal) and daisy (34, 55 or 89 petals). The number of petals of these flowers just constitutes a series of numbers in Fibonacci series. References:

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