13+23+33+...+n3=(n(n+1)2)2
The sum of the cubes of the first n natural numbers is given by the formula: ((n(n+1)/2)^2 = (n^2(n+1)^2)/4 Therefore, the sum of the cubes of the first n natural numbers is ((n^2(n+1)^2)/4).
Have a look at https://mathschallenge.net/library/number/sum_of_cubes
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