Presburger arithmetic, or linear integer arithmetic, is known to have decision procedures that work in triply exponential time.
Jointly with M. Benedikt (Oxford) and A. Mansutti (IMDEA Software Institute), we have recently considered two decidable extensions of Presburger arithmetic: with the power function and with the predicate for the set of powers of 2. No elementary decision procedures were known for these two theories.
In this talk, I will introduce this work and outline ideas behind our results. Namely, we have shown that existence of solutions over N to systems of linear equations and constraints of the form $y = 2^x$ can be decided in nondeterministic exponential time. Also, linear integer arithmetic extended with a predicate for powers of 2 can be decided in triply exponential time.