Text: There isn't a "test" that you can apply to an integer to determine whether it is a cube of an integer, other than looking it up in a table. Perhaps you are asking for an algorithm to calculate the cube root of any positive number. If a is the number you want the cube root of, make a guess and call it g. The next guess is G = (2/3)*g + (1/3)*(a/(g^2)). Repeat this until the cube root is found to desired accuracy. If a = 8, for example, suppose our first guess is 3. Using the above formula, here are the successive guesses: g1 = 3 g2 = 2.2962962963 g3 = 2.03658740252 g4 = 2.00065335855 g5 = 2.00000021335 g6 = 2.00000000000 ( to the accuracy of my calculator)

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