# Questions tagged [automata-theory]

Automata Theory, including abstract machines, grammars, parsing, grammatical inference, transducers, and finite-state techniques

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### Are finite state automata with one register storage equivalent to push down automata?

This is a very simple question, but I couldn't find a reference and I just wanted to check my facts. I was looking for a state machine similar to pushdown automata but where the stack is restricted to ...
62 views

### Algorithms to synthesize optimal plans satisfying temporal logic constraints

I know how NuSMV can be applied on a model to check if certain temporal logic statements are satisfied, particularly LTL. I also know of the LTL to BA conversion routines available online. I am ...
51 views

### Palindrome language and Finite Automata Machines [closed]

I'm a grad student in math. I'm unaware of available literature in theoretical computer science, so require suggestions for books. Here are the two topics I'm interested in exploring. 1) A complete ...
40 views

### Question About Turing Machine Computability [closed]

If p is a Turing machine then L(p) = {x | p(x) = yes}. Let A = {p | p is a Turing machine and L(p) is a finite set}. Is A computable? Justify your answer. So I'm trying to figure out how to solve ...
62 views

### Rational power series over $\mathbb N \cup \{\infty\}$, rationality of singular part

Let $\Sigma$ be a finite alphabet, and consider the formel power series over $\Sigma$ considered as non-commuting variables with coefficients in the semiring $\mathcal N := \mathbb N \cup \{\infty\}$ ...
457 views

### Equality Constraints over Sets with Tree Automata

Tree Automata can be used to model sets of values of a Herbrand Universe, for example, to model possible values in a functional program. Systems of subtype constraints over set expressions have ...
102 views

### Relation between MDPs and non-deterministic finite automatons

I'm confused as to the relation (computability-wise) between markov decision processes and NFAs. Are finite state MDPs expressible as regular grammars? If so, are markov decision processes thus ...
102 views

### Convenient forms of Turing machines

Let us suppose that I have defined a new convenient form of the Turing machine for processing of some specific sort of commonly used structures. This form of TM contains some specific features ...
175 views

### Hysteresis in finite automata

The concept of hysteresis seems well suited to describe and distinguish finite automata: "Hysteresis is the dependence of the state of a system on its history." (Wikipedia, Hysteresis) "[The ...
127 views

### Why is an automaton on finite words co-deterministic iff its transitions are co-deterministic

In the article Automata and semigroups recognizing infinite words an automaton is specified by $\mathcal A = (Q, A, E, I, F)$ where $I$ is a set of initial states and $F$ a set of final states, $Q$ ...
86 views

### Which paper first showed that any context-free grammar (CFG) is equivalent to some CFG in Chomsky normal form?

Which paper first showed that any context-free grammar (CFG) is equivalent to some CFG in Chomsky normal form? I cannot find an reference.
94 views

### Properties of the number of copies of an NFA in each state

For an NFA $A$ with $n$ states and a word $w$, we can associate an $n$-dimensional vector $v_w$ with entries in $\mathbb{N}\cup\{0\}$ denoting the number of copies of the NFA in each state after ...
73 views

### Vector representation of probabilistic automaton

Suppose we have $N$ states $q_i$, $0\leq i<N$ Suppose we have $N\times N$ probability matrix $p_{ij}$, $0\leq i<N$, $0\leq j<N$, And suppose a machine, which is being in state $q_i$ then ...
91 views

### Automatic structures/functions: Is (Z,+) under a unary representation automatic?

The group $(\mathbb{Z}, +)$ is automatic (ala Khoussainov) when using the "standard" representation in a decimal base. But if I want to use a different representation of Z, encoding my integers with ...
190 views

### Dynamic k-shortest paths in a weighted transducer

I'm looking for references relating to dynamically computing the k-shortest output paths through a stochastic, acyclic, weighted transducer that is being constructed on-the-fly. In this scenario ...
144 views

### Density of black cells in rule 110 cellular automata [closed]

Is there a way to compute the limit of the ratio (number of black cells)/(number of white cells), in the rule 110 or rule 30 automaton? With initial state = 1 black cell. Simulation of first 120000 ...
637 views

### Strategy for grammar derivation of a formal language

I wonder, whether there is any strategy/ies for grammar derivation of a formal language. I'd be thankful, if you give me some hints, tips on how should one "think" trying to find a grammar. I'm ...
180 views

### Edit-Distance of weighted automata

I'm trying to understand "Edit Distance of Weighted Automata" by Mehryar Mohri: [83], [93] and [99] at http://www.cs.nyu.edu/~mohri/pub/ (they are virtually identical so which of them doesn't matter). ...
174 views

### iterations of a $\epsilon$-FSM transducer on a tape as equivalent to a TM computation

A question partly inspired by a recent question[1] on the utility of FSMs: Years ago noticed the following property of FSM transducers with $\epsilon$-transitions (which allow an "empty" transition ...
256 views

### is determining an unknown CFL from intersection of two CFLs decidable?

this problem was asked over a week ago on cs.se now with 7v and no answers so far, ie still "open". (there are many somewhat related problems/near variants re CFLs but its not obvious how to reduce it ...
181 views

### Does every regular language contains a strictly locally testable language?

Let $L$ be an infinite regular language, then does there exists a strictly locally testable infinite language $P$ such that $P \subseteq L$?
461 views

### Theta functions of automata relations

Let $A,B$ be two automata over the same alphabet $\Sigma$; they are supposed to be complete, strongly connected DFAs. We denote by $._A$ (resp. $._B$) the action induced by $\Sigma^*$ over $Q(A)$, i.e....
212 views

### A fsm with temporal events

I have defined a finite state machine Q = {Σ, S, s0, δ, F} where Σ = {'[r]equest', '[o]ut', '[i]n', '[e]nd'} S = {'[R]eady', '[I]nitiating', '[W]aiting', 'Re[C]eived', 'Re[S]...
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### Question about Mapping Reductions (Clarify Example)

I cannot for the life of me wrap my head around these reductions. Specifically, the example I'm wrestling with: ...
203 views

### Where does a C-like language without heaps belong in the automata hierarchy?

Assume that the language C', unlike C, has well-defined semantics, but has similar features: pointers and manual memory management through malloc and free. Assume that C'' is the same as C' without ...
131 views

### finite automata under morphism [closed]

Given two (deterministic) finite automata $A, B$ over $\Sigma$, a mapping $h:\Sigma\rightarrow \Sigma'$ Naturally $h$ can be extended to a mapping in $\Sigma^*\rightarrow \Sigma'^*$ which is denoted ...
158 views

### Implicit Non-deterministic Buchi determinization

I am doing implicit Buchi determination for LTL logic in hardware where the combinational logic represents the set of states. But instead of using acceptance states, I am using final state (as in ...
86 views

### Difference between locally testable and it's boolean closure

A language $L$ is called i) locally testable in the strict sense iff there exists $P, S, I \subseteq X^*$ such that  w \in L \mbox{ iff } pref^k(w) \in P, suffix^k(w) \in S, infix^k(w) \subseteq I....
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### Show that, for any languages L1 and L2, we have (1). L1L1^* = L1^*L1L1^* [migrated]

I am very confused on how to solve this problem. I know L star is 0 or more times, but proving it I do not know what to do
58 views

### Information theory for Mathematical Physics [duplicate]

What are some good introductory texts on information theory for someone who is classically trained in mathematical physics? Unfortunately my abilities in computer sciences and formal logic are next ...
68 views

### Language recongized by a “quasi realtime register machine”?

Counter machines are very powerful. Even two counters suffice for making these Turing complete. But, in simulating a Turing machine the counter machine encodes in its integers a large amount of data. ...
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### Questions about the definition of the Quantum Turing Machine

I am trying to have a better understanding of the definition of the Quantum Turing Machine. My questions: If the output of a quantum program is the eigenvalue of the ground state of a Hamiltonian ...
78 views

### Generalizing a set of positive and negative examples through DFAs [duplicate]

Possible Duplicate: Is finding the minimum regular expression an NP-complete problem? Let $\Sigma$ be an alphabet. Let $P$ and $N$ (the set of positive and negative examples) be two disjoint ...
210 views

### formal definition of “flowcharts”

I am looking for a formal definition of so-called "flowcharts" used as representation of programs or business processes. Is there some good one around ? Thx JCLL
75 views

### Is there an inherently ambiguous language which can not be recognized by Deterministic LBA?

Is there inherently ambiguous language which can not be recognized by Deterministic LBA? For example, $L=\{wv: w,v=(x|y)^*, w=w^R,v=v^R\}$, is there any deterministc LBA that recognizes $L$ ?
95 views

### What is the formal definition of a stacked based finite state machine?

The formal definition of a finite state machine is as follows: A FSM is a quintuple: ($I$, $S$, $S$0, $T$, $F$) $I$ - finite, non-empty input set $S$ - finite, non-empty state set $S$0 - initial state ...
86 views

### Issue in understanding conditional likelihood for a producton rule

The Equation1 in paper in link explains how to assign probability to a production rule. Fig1 explains with an example. Now, I have a problem in understanding how to work with this formula since it ...
1k views

### How to XOR automata? [closed]

Say we have 3 DFAs. We know how to OR, AND, or NOT them. But how does one XOR them? There is not one single mention of this online. x XOR y XOR z = ((x|y)(~x|y)|z) (~((x|y)(~x|y))|z). This is way too ...
122 views

### Looking for menu-driven coding editor based on a programming language state machine [closed]

I'd like to know whether an application development environment exists that uses a menu-driven coding editor that employs a programming language state machine. This would mean that commands, variable ...
46 views

### Push Down Automata [closed]

Can we put more than one element in stack at a time. Actually I am asking that this transition function is valid for PDA: ∆(q,a,z)=(q',aaz) Where: q and q' are states a is input symbol z is starting ...
94 views

### When designing a DFA, am I allowed to design two separate Machines and perform an Intersection on them? [closed]

I am trying to design a DFA s.t. The set of strings in x ∈ {0, 1}∗ such that the number of zeros is a multiple of 3 and the number of one's is even. My idea was to create two Machines M1 = (Q1, Σ, δ1,...
107 views

### Constructing automata with the same traces, but where a CTL-formula is not equally satisfied [closed]

Hard to put this question in a short title. As part of a self-exercise, I'm trying to solve 6.15b of Principles of Model Checking by Baier and Katoen. You're supposed to prove that there does not ...
118 views

### How does “δ:Q×Σ→Q” read in the definition of a DFA (deterministic finite acceptor)? [closed]

How do you say "δ:Q×Σ→Q" in English? Describing what "×" and "→" mean would also help.
362 views

### Can I show algebraically that this regular expression accepts all binary strings?

The task is to prove that (0+1)* and 0*(1.0*)* are equivalent. 1. http://rubular.com/r/K9Hp9tU6px 2. http://rubular.com/r/N8VpoEcch4 EDIT: Forgot that + was ambiguous here! I want to prove that the ...
381 views

### Can every non-deterministic finite automate be changed into one with only one acceptance state? [closed]

How can an arbitrary non-deterministic finite automate be converted into one with only one accept stage? If so, what is the proof that this can always be done?
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### DPDA with parameterized states

I'm considering an extension of Sublime Text's syntax definition format. A syntax definition is, in essence, a specification of a deterministic pushdown automaton. I would like to extend the system to ...
635 views

I'm trying to find a formal proof of the following fact: Given a context-free language, say $L_1$, and a context-sensitive language, say $L_2$, it is NOT decidable if their intersection is empty ($... 1answer 212 views ### Writing a regular expression for character set$\Sigma = \{a,b,(,)\}$that not have a parenthesis inside a parenthesis [closed] Let character set$\Sigma=\{a,b,(,)\}$. I want to write a regular expression for the language$L$that does not have a parenthesis inside a parenthesis. For example,$(abaab)(bbbaa) \in L$, while$(...
Let $L$ be a regular language with the alphabet $\Sigma$. I'm trying to find an algorithm to tell whether $L=\Sigma^{*}$, whether $L$ accepts all strings in its alphabet. I think this algorithm uses ...