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Let P(n) be the statement
When n=1, LHS
Since LHS = RHS, P(1) is true.
Assume P(k) is true for some k,
Want to show P(k+1) is true,
Since P(1) is true, P(k) is true P(k+1) is true, hence, by Mathematical Induction, P(n) is true for all
Least n = 499