The Political Action Committee for computational complexity research.
The class of problems for which there exists a DiffAC0 function f such that the answer is "yes" on input x if and only if f(x)>0.
Equals TC0 and C=AC0 under logspace uniformity [ABL98].
The class of problems for which there exists a DiffAC0 function f such that the answer is "yes" on input x if and only if f(x)=0.
Equals TC0 and PAC0 under logspace uniformity [ABL98].