This function i unimodal and continuous, but the global optimum is hard to find, because of independence through the term (x_(i+1) - x_i*x_i)^2 between contiguous parameters.
Rosenbrock's function within the co-domain -5 <= x <= 5.
The global optimum is located in a prabolic formed valley (among the curve x^2 = x_1^2), which has a flatten ground.
The function close to its global optimum, which is: f(x) = f(1, 1, ... , 1) = 0.
Rosenbrock' function is not symmetric, not convex and not linear.
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