Majority function

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The majority function is a logic function from n inputs to one output, defined as follows: If more inputs are TRUE than are FALSE, then the majority function returns TRUE. Otherwise, the function returns FALSE.

Representing TRUE as 1 and FALSE as 0 provides this alternate definition: \operatorname{Majority} \left ( p_1,...,p_n \right ) =  \left \lfloor \frac{1}{2} +  \frac{\sum_{i=1}^n  p_i - 1/2}{n} \right \rfloor

The "- 1/2" in the formula serves to break ties in favor of FALSE.

A major result in circuit complexity asserts that this function cannot be computed by AC0 circuits of subexponential size.