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in the book "Introduction to algorithms"(CLRS) page 49 it says:
"The number of anonymous functions in an expression is understood to be equal to the number of times the asymptotic notation appears. For example, in the expression:
there is only a single anonymous function (a function of i). This expression is thus not the same as $O(1) + O(2) + O(3) + ... + O(n)$, which doesn’t really have a clean interpretation."
what is the difference between these 2 equitions and how should interpret each one??