0 votes 0 votes Can someone construct a PDA for ai bj where i not equal to 3j+1 ? Is it NPDA or DPDA? Theory of Computation pushdown-automata theory-of-computation minimal-state-automata context-free-language + – Xylene asked Nov 24, 2016 • retagged Jul 4, 2017 by Arjun Xylene 477 views answer comment Share Follow See 1 comment See all 1 1 comment reply Ashwin Kulkarni commented Jan 1, 2018 reply Follow Share It is DPDA. Push, 4 a's instead for 1 a, and try to 4 b's for each b. if at last a's or b's will be remain then accepted. 0 votes 0 votes Please log in or register to add a comment.