/kloc-Fibonacci, a famous Italian mathematician in the third century, raised a very interesting question: rabbits can give birth two months after birth, and just one pair (a female and a male) is born every month. If you raise a pair of newborn rabbits (a female and a male), how many pairs of rabbits will there be in a year? After popularization, you can ask the rabbit logarithm an= after n months. The sequence {an} has aroused great interest and is called Fibonacci sequence. It is easy to see that a 1= 1, a2=2, a3=3, a3=5, a4=8, a5= 13 ... The recursive formula an = an-1+was not discovered until 1634. 1963 published Fibonacci Society and Fibonacci Quarterly. Fibonacci sequence is widely used, which is closely related to plant growth, geometric pattern, golden section, Yang Hui triangle, matrix operation, indefinite equation, optimization method, computer science and so on. Its peculiar nature and various changes have left a deep impression on math lovers. Its generalization-linear recursive sequence has become the main research content of combinatorial mathematics and has a wider application. In fact, it permeates almost all branches of mathematics, such as number theory, algebra, graph theory, differential equations, difference equations, numerical analysis, operational research, game theory, probability statistics, function theory, geometry theory and so on. Especially in 1970, Russian mathematician Matijasevic successfully solved the famous tenth problem of Hilbert-the discrimination of the solvability of Diophantine equation. The answer is that its general algorithm does not exist, and it is more popular and receives rave reviews.