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The recursive formula of the Fibonacci sequence: F_1 = 1, F_2 = 1, F_{n+2} = F_{n+1} + F_n. The next number of the Fibonacci sequence is found by adding up the two numbers before it. The general formula of the Fibonacci sequence: F_n = (1 / square root of 5) * (1 + square root of 5 / 2)^n - (1 / square root of 5) * (1 - square root of 5 / 2)^n.