Undecidable language problems
104626
Undecidable language problems.
111349
Finite automaton that recognizes the empty language $\emptyset$
5220
Immutability, Association and typing
147924
Math problems that are impossible to solve
21254
Formal language: Proving the reverse operation on a word through induction
10519
Describe in English a Turing machine that semidecides the following language - Is this solution correct?
117254
Solving a implicit, recursive function
69748
Semi-Ambiguous Combinatorics Problem
115402
Fixing Catastrophic Backtracking in Regular Expression
74839
Catalan numbers: bijection between applications of a binary operator and Dyck words.
67683
Building logical criteria (with AND , OR, etc)
107975
Show that the class of regular languages is closed under shuffle
67490
Restricing domains for universal and existential quantifiers
85799
Finding languages such that $L_{1} \subseteq L_{2} \subseteq L_{3}$ where $L_{1}, L_{3} \notin \mathbb{R}$, $L_{2} \in \mathbb{R}$
76597
Examples of provably${}^n$ unprovable statements
86064
Argument completions for user-defined functions
114256
More Generating Functions problems