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The F(R) theory of gravity has drawn much attention from cosmologists in recent years,since it elegantly solves the cosmic puzzle in connection with dark energy,unifies early inflation with late time cosmic acceleration,admits the Newtonian limit and passes the solar test singlehandedly [see Ref.[1] for recent and thorough reviews].However,in order to select a particular form of F(R) out of an indefinitely large number of curvature invariant terms,Noether symmetry was invoked as a selection rule by several authors.[2-9] Results in a nutshell are as follows:(i) Noether symmetry does not admit anything other than F(R) ∝ R3/2,along with a conserved current d/at (a√R) in a Robertson-Walker metric.