'needs exponential number of steps in a non-increasing f-sequence.
x_0 = (-1,1,...,1)
See Jarre (2011) "On Nesterov\'s Smooth Chebyshev-Rosenbrock Function"'

def rosen_nesterov(self, x, rho=100):

    f = (0.25 * ((x[0] - 1) ** 2))
    f += (rho * sum((((x[1:] - (2 * (x[:(-1)] ** 2))) + 1) ** 2)))
    return f
