Finite automaton that recognizes the empty language $emptyset$
up vote
10
down vote
favorite
Since the language $L = emptyset$ is regular, there must be a finite automaton that recognizes it. However, I'm not exactly sure how one would be constructed. I feel like the answer is trivial. Can someone help me out?
computer-science formal-languages automata
add a comment |
up vote
10
down vote
favorite
Since the language $L = emptyset$ is regular, there must be a finite automaton that recognizes it. However, I'm not exactly sure how one would be constructed. I feel like the answer is trivial. Can someone help me out?
computer-science formal-languages automata
Write "This automaton is...." or "These automata are....". (I fixed this in the question.)
– Michael Hardy
Mar 26 '13 at 3:24
add a comment |
up vote
10
down vote
favorite
up vote
10
down vote
favorite
Since the language $L = emptyset$ is regular, there must be a finite automaton that recognizes it. However, I'm not exactly sure how one would be constructed. I feel like the answer is trivial. Can someone help me out?
computer-science formal-languages automata
Since the language $L = emptyset$ is regular, there must be a finite automaton that recognizes it. However, I'm not exactly sure how one would be constructed. I feel like the answer is trivial. Can someone help me out?
computer-science formal-languages automata
computer-science formal-languages automata
edited Mar 30 '13 at 0:26
Tara B
4,8601436
4,8601436
asked Mar 25 '13 at 22:32
user68486
51113
51113
Write "This automaton is...." or "These automata are....". (I fixed this in the question.)
– Michael Hardy
Mar 26 '13 at 3:24
add a comment |
Write "This automaton is...." or "These automata are....". (I fixed this in the question.)
– Michael Hardy
Mar 26 '13 at 3:24
Write "This automaton is...." or "These automata are....". (I fixed this in the question.)
– Michael Hardy
Mar 26 '13 at 3:24
Write "This automaton is...." or "These automata are....". (I fixed this in the question.)
– Michael Hardy
Mar 26 '13 at 3:24
add a comment |
4 Answers
4
active
oldest
votes
up vote
11
down vote
One state, non-accepting, and no transitions. (That’s an NFA; if you want a DFA, have one transition from the state to itself for each letter of whatever alphabet is specified.)
1
Can a finite automata have no accept states at all?
– user68486
Mar 25 '13 at 22:40
2
@user68486: Yes, it can: the set of acceptor states can be any subset of the set of states.
– Brian M. Scott
Mar 25 '13 at 22:42
Can you please elaborate, why the NFA can have no transitions, but the DFA must have a transition for every letter in the alphabet?
– de_dust
Oct 19 '17 at 9:24
for a moment I felt we shouldnt need any state (invisible FA :p)...seems thats not allowed...
– anir
Dec 23 '17 at 15:57
add a comment |
up vote
6
down vote
You have only one state $s$ that is initial, but not accepting with loops $s overset{alpha}{rightarrow} s$ for any letter $alpha in Sigma$ (with non-deterministic automaton you can even skip the loops, i.e. the transition relation would be empty).
I hope this helps ;-)
add a comment |
up vote
1
down vote
Given language is "empty language".We have to construct a finite automata for this language.In general we consider "the construction of finite automata" as "the construction of DFA".So....{Let us assume input symbol as 'a' and 'b'}
(a)If we take one state(initial state) and don't show any transition of any input symbol over this state,then this structure will not be a DFA because in a DFA there should be a transition of all input symbol over each state.
(b)If we take one state(initial state) and show the transition of both input symbol 'a' and 'b' over this state, then also this will not be a DFA because there should be a final state.
(c)If we take one state(initial state) and show the transition of both input symbol 'a' and 'b' over this state,and making this state final also then this FA will not be acceptor of "empty language".
(d)If we take one initial state 'A'(not making final it) showing the transition of both input symbol over 'A' itself AND taking one another state 'B'(as final)showing the transition of both input symbol over the "transion edge" from final state 'B' to initial state 'A'('B'is UNREACHABLE STATE here).Then this structure will be a DFA but not minimal DFA because in minimal DFA we remove UNREACHABLE STATE.
(e)similarly we cannot take concept of dead state in construction of minimal DFA.
SO NOW THE EXACT SOLUTION IS :-
" TAKE ONE INITIAL STATE 'A'(not making final it) and ONE ANOTHER STATE 'B'(making it final) and SHOW transition of both input symbol 'a' and 'b' over both state A' and 'B'. BUT don't connect both states with any transition edge.
This is the desired minimal DFA which accepts "empty language".
add a comment |
up vote
1
down vote
This is the DFA that iterates over (0|1)* but does not accept anything (not even empty string).
You've just said "accept empty string" and then "does not accept anything". Can you explain it better?
– JB-Franco
Mar 15 '17 at 22:24
1
@JB-Franco Acceptance of empty thing == not accepting anything! I think you are aware of "empty language", which means "no string", So to rephrase, "accepts empty string" == "accepts no string" == "does not accepts anything". If you still have problems, please comment.
– lU5er
Mar 17 '17 at 12:17
Thanks! - The fact you have explained in the above about DFA accepting empty string, can be related to what I have asked here: Why in a DFA the empty string distinguishes any accept state from any reject state?
– JB-Franco
Mar 17 '17 at 19:41
1
This answer is wrong because "accepts empty string" and "accepts no string" are not the same! The NFA with only one state and no transitions accepts no strings if the state is non-accepting, and the empty string (but no other strings) if the state is accepting. Similarly, a DFA can accept only the empty string and no others by having a start state which is accepting and then all transitions point to a non-accepting trap state like the one in this answer.
– Benjamin Cosman
May 29 '17 at 16:13
@BenjaminCosman, answer me one thing, what do you mean byempty string
?
– lU5er
May 30 '17 at 17:25
|
show 9 more comments
4 Answers
4
active
oldest
votes
4 Answers
4
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
11
down vote
One state, non-accepting, and no transitions. (That’s an NFA; if you want a DFA, have one transition from the state to itself for each letter of whatever alphabet is specified.)
1
Can a finite automata have no accept states at all?
– user68486
Mar 25 '13 at 22:40
2
@user68486: Yes, it can: the set of acceptor states can be any subset of the set of states.
– Brian M. Scott
Mar 25 '13 at 22:42
Can you please elaborate, why the NFA can have no transitions, but the DFA must have a transition for every letter in the alphabet?
– de_dust
Oct 19 '17 at 9:24
for a moment I felt we shouldnt need any state (invisible FA :p)...seems thats not allowed...
– anir
Dec 23 '17 at 15:57
add a comment |
up vote
11
down vote
One state, non-accepting, and no transitions. (That’s an NFA; if you want a DFA, have one transition from the state to itself for each letter of whatever alphabet is specified.)
1
Can a finite automata have no accept states at all?
– user68486
Mar 25 '13 at 22:40
2
@user68486: Yes, it can: the set of acceptor states can be any subset of the set of states.
– Brian M. Scott
Mar 25 '13 at 22:42
Can you please elaborate, why the NFA can have no transitions, but the DFA must have a transition for every letter in the alphabet?
– de_dust
Oct 19 '17 at 9:24
for a moment I felt we shouldnt need any state (invisible FA :p)...seems thats not allowed...
– anir
Dec 23 '17 at 15:57
add a comment |
up vote
11
down vote
up vote
11
down vote
One state, non-accepting, and no transitions. (That’s an NFA; if you want a DFA, have one transition from the state to itself for each letter of whatever alphabet is specified.)
One state, non-accepting, and no transitions. (That’s an NFA; if you want a DFA, have one transition from the state to itself for each letter of whatever alphabet is specified.)
answered Mar 25 '13 at 22:38
Brian M. Scott
453k38504904
453k38504904
1
Can a finite automata have no accept states at all?
– user68486
Mar 25 '13 at 22:40
2
@user68486: Yes, it can: the set of acceptor states can be any subset of the set of states.
– Brian M. Scott
Mar 25 '13 at 22:42
Can you please elaborate, why the NFA can have no transitions, but the DFA must have a transition for every letter in the alphabet?
– de_dust
Oct 19 '17 at 9:24
for a moment I felt we shouldnt need any state (invisible FA :p)...seems thats not allowed...
– anir
Dec 23 '17 at 15:57
add a comment |
1
Can a finite automata have no accept states at all?
– user68486
Mar 25 '13 at 22:40
2
@user68486: Yes, it can: the set of acceptor states can be any subset of the set of states.
– Brian M. Scott
Mar 25 '13 at 22:42
Can you please elaborate, why the NFA can have no transitions, but the DFA must have a transition for every letter in the alphabet?
– de_dust
Oct 19 '17 at 9:24
for a moment I felt we shouldnt need any state (invisible FA :p)...seems thats not allowed...
– anir
Dec 23 '17 at 15:57
1
1
Can a finite automata have no accept states at all?
– user68486
Mar 25 '13 at 22:40
Can a finite automata have no accept states at all?
– user68486
Mar 25 '13 at 22:40
2
2
@user68486: Yes, it can: the set of acceptor states can be any subset of the set of states.
– Brian M. Scott
Mar 25 '13 at 22:42
@user68486: Yes, it can: the set of acceptor states can be any subset of the set of states.
– Brian M. Scott
Mar 25 '13 at 22:42
Can you please elaborate, why the NFA can have no transitions, but the DFA must have a transition for every letter in the alphabet?
– de_dust
Oct 19 '17 at 9:24
Can you please elaborate, why the NFA can have no transitions, but the DFA must have a transition for every letter in the alphabet?
– de_dust
Oct 19 '17 at 9:24
for a moment I felt we shouldnt need any state (invisible FA :p)...seems thats not allowed...
– anir
Dec 23 '17 at 15:57
for a moment I felt we shouldnt need any state (invisible FA :p)...seems thats not allowed...
– anir
Dec 23 '17 at 15:57
add a comment |
up vote
6
down vote
You have only one state $s$ that is initial, but not accepting with loops $s overset{alpha}{rightarrow} s$ for any letter $alpha in Sigma$ (with non-deterministic automaton you can even skip the loops, i.e. the transition relation would be empty).
I hope this helps ;-)
add a comment |
up vote
6
down vote
You have only one state $s$ that is initial, but not accepting with loops $s overset{alpha}{rightarrow} s$ for any letter $alpha in Sigma$ (with non-deterministic automaton you can even skip the loops, i.e. the transition relation would be empty).
I hope this helps ;-)
add a comment |
up vote
6
down vote
up vote
6
down vote
You have only one state $s$ that is initial, but not accepting with loops $s overset{alpha}{rightarrow} s$ for any letter $alpha in Sigma$ (with non-deterministic automaton you can even skip the loops, i.e. the transition relation would be empty).
I hope this helps ;-)
You have only one state $s$ that is initial, but not accepting with loops $s overset{alpha}{rightarrow} s$ for any letter $alpha in Sigma$ (with non-deterministic automaton you can even skip the loops, i.e. the transition relation would be empty).
I hope this helps ;-)
answered Mar 25 '13 at 22:39
dtldarek
32k74399
32k74399
add a comment |
add a comment |
up vote
1
down vote
Given language is "empty language".We have to construct a finite automata for this language.In general we consider "the construction of finite automata" as "the construction of DFA".So....{Let us assume input symbol as 'a' and 'b'}
(a)If we take one state(initial state) and don't show any transition of any input symbol over this state,then this structure will not be a DFA because in a DFA there should be a transition of all input symbol over each state.
(b)If we take one state(initial state) and show the transition of both input symbol 'a' and 'b' over this state, then also this will not be a DFA because there should be a final state.
(c)If we take one state(initial state) and show the transition of both input symbol 'a' and 'b' over this state,and making this state final also then this FA will not be acceptor of "empty language".
(d)If we take one initial state 'A'(not making final it) showing the transition of both input symbol over 'A' itself AND taking one another state 'B'(as final)showing the transition of both input symbol over the "transion edge" from final state 'B' to initial state 'A'('B'is UNREACHABLE STATE here).Then this structure will be a DFA but not minimal DFA because in minimal DFA we remove UNREACHABLE STATE.
(e)similarly we cannot take concept of dead state in construction of minimal DFA.
SO NOW THE EXACT SOLUTION IS :-
" TAKE ONE INITIAL STATE 'A'(not making final it) and ONE ANOTHER STATE 'B'(making it final) and SHOW transition of both input symbol 'a' and 'b' over both state A' and 'B'. BUT don't connect both states with any transition edge.
This is the desired minimal DFA which accepts "empty language".
add a comment |
up vote
1
down vote
Given language is "empty language".We have to construct a finite automata for this language.In general we consider "the construction of finite automata" as "the construction of DFA".So....{Let us assume input symbol as 'a' and 'b'}
(a)If we take one state(initial state) and don't show any transition of any input symbol over this state,then this structure will not be a DFA because in a DFA there should be a transition of all input symbol over each state.
(b)If we take one state(initial state) and show the transition of both input symbol 'a' and 'b' over this state, then also this will not be a DFA because there should be a final state.
(c)If we take one state(initial state) and show the transition of both input symbol 'a' and 'b' over this state,and making this state final also then this FA will not be acceptor of "empty language".
(d)If we take one initial state 'A'(not making final it) showing the transition of both input symbol over 'A' itself AND taking one another state 'B'(as final)showing the transition of both input symbol over the "transion edge" from final state 'B' to initial state 'A'('B'is UNREACHABLE STATE here).Then this structure will be a DFA but not minimal DFA because in minimal DFA we remove UNREACHABLE STATE.
(e)similarly we cannot take concept of dead state in construction of minimal DFA.
SO NOW THE EXACT SOLUTION IS :-
" TAKE ONE INITIAL STATE 'A'(not making final it) and ONE ANOTHER STATE 'B'(making it final) and SHOW transition of both input symbol 'a' and 'b' over both state A' and 'B'. BUT don't connect both states with any transition edge.
This is the desired minimal DFA which accepts "empty language".
add a comment |
up vote
1
down vote
up vote
1
down vote
Given language is "empty language".We have to construct a finite automata for this language.In general we consider "the construction of finite automata" as "the construction of DFA".So....{Let us assume input symbol as 'a' and 'b'}
(a)If we take one state(initial state) and don't show any transition of any input symbol over this state,then this structure will not be a DFA because in a DFA there should be a transition of all input symbol over each state.
(b)If we take one state(initial state) and show the transition of both input symbol 'a' and 'b' over this state, then also this will not be a DFA because there should be a final state.
(c)If we take one state(initial state) and show the transition of both input symbol 'a' and 'b' over this state,and making this state final also then this FA will not be acceptor of "empty language".
(d)If we take one initial state 'A'(not making final it) showing the transition of both input symbol over 'A' itself AND taking one another state 'B'(as final)showing the transition of both input symbol over the "transion edge" from final state 'B' to initial state 'A'('B'is UNREACHABLE STATE here).Then this structure will be a DFA but not minimal DFA because in minimal DFA we remove UNREACHABLE STATE.
(e)similarly we cannot take concept of dead state in construction of minimal DFA.
SO NOW THE EXACT SOLUTION IS :-
" TAKE ONE INITIAL STATE 'A'(not making final it) and ONE ANOTHER STATE 'B'(making it final) and SHOW transition of both input symbol 'a' and 'b' over both state A' and 'B'. BUT don't connect both states with any transition edge.
This is the desired minimal DFA which accepts "empty language".
Given language is "empty language".We have to construct a finite automata for this language.In general we consider "the construction of finite automata" as "the construction of DFA".So....{Let us assume input symbol as 'a' and 'b'}
(a)If we take one state(initial state) and don't show any transition of any input symbol over this state,then this structure will not be a DFA because in a DFA there should be a transition of all input symbol over each state.
(b)If we take one state(initial state) and show the transition of both input symbol 'a' and 'b' over this state, then also this will not be a DFA because there should be a final state.
(c)If we take one state(initial state) and show the transition of both input symbol 'a' and 'b' over this state,and making this state final also then this FA will not be acceptor of "empty language".
(d)If we take one initial state 'A'(not making final it) showing the transition of both input symbol over 'A' itself AND taking one another state 'B'(as final)showing the transition of both input symbol over the "transion edge" from final state 'B' to initial state 'A'('B'is UNREACHABLE STATE here).Then this structure will be a DFA but not minimal DFA because in minimal DFA we remove UNREACHABLE STATE.
(e)similarly we cannot take concept of dead state in construction of minimal DFA.
SO NOW THE EXACT SOLUTION IS :-
" TAKE ONE INITIAL STATE 'A'(not making final it) and ONE ANOTHER STATE 'B'(making it final) and SHOW transition of both input symbol 'a' and 'b' over both state A' and 'B'. BUT don't connect both states with any transition edge.
This is the desired minimal DFA which accepts "empty language".
answered Aug 10 '15 at 16:49
Salman Ahmad
111
111
add a comment |
add a comment |
up vote
1
down vote
This is the DFA that iterates over (0|1)* but does not accept anything (not even empty string).
You've just said "accept empty string" and then "does not accept anything". Can you explain it better?
– JB-Franco
Mar 15 '17 at 22:24
1
@JB-Franco Acceptance of empty thing == not accepting anything! I think you are aware of "empty language", which means "no string", So to rephrase, "accepts empty string" == "accepts no string" == "does not accepts anything". If you still have problems, please comment.
– lU5er
Mar 17 '17 at 12:17
Thanks! - The fact you have explained in the above about DFA accepting empty string, can be related to what I have asked here: Why in a DFA the empty string distinguishes any accept state from any reject state?
– JB-Franco
Mar 17 '17 at 19:41
1
This answer is wrong because "accepts empty string" and "accepts no string" are not the same! The NFA with only one state and no transitions accepts no strings if the state is non-accepting, and the empty string (but no other strings) if the state is accepting. Similarly, a DFA can accept only the empty string and no others by having a start state which is accepting and then all transitions point to a non-accepting trap state like the one in this answer.
– Benjamin Cosman
May 29 '17 at 16:13
@BenjaminCosman, answer me one thing, what do you mean byempty string
?
– lU5er
May 30 '17 at 17:25
|
show 9 more comments
up vote
1
down vote
This is the DFA that iterates over (0|1)* but does not accept anything (not even empty string).
You've just said "accept empty string" and then "does not accept anything". Can you explain it better?
– JB-Franco
Mar 15 '17 at 22:24
1
@JB-Franco Acceptance of empty thing == not accepting anything! I think you are aware of "empty language", which means "no string", So to rephrase, "accepts empty string" == "accepts no string" == "does not accepts anything". If you still have problems, please comment.
– lU5er
Mar 17 '17 at 12:17
Thanks! - The fact you have explained in the above about DFA accepting empty string, can be related to what I have asked here: Why in a DFA the empty string distinguishes any accept state from any reject state?
– JB-Franco
Mar 17 '17 at 19:41
1
This answer is wrong because "accepts empty string" and "accepts no string" are not the same! The NFA with only one state and no transitions accepts no strings if the state is non-accepting, and the empty string (but no other strings) if the state is accepting. Similarly, a DFA can accept only the empty string and no others by having a start state which is accepting and then all transitions point to a non-accepting trap state like the one in this answer.
– Benjamin Cosman
May 29 '17 at 16:13
@BenjaminCosman, answer me one thing, what do you mean byempty string
?
– lU5er
May 30 '17 at 17:25
|
show 9 more comments
up vote
1
down vote
up vote
1
down vote
This is the DFA that iterates over (0|1)* but does not accept anything (not even empty string).
This is the DFA that iterates over (0|1)* but does not accept anything (not even empty string).
edited Jun 7 '17 at 23:17
answered Dec 21 '16 at 20:46
lU5er
205111
205111
You've just said "accept empty string" and then "does not accept anything". Can you explain it better?
– JB-Franco
Mar 15 '17 at 22:24
1
@JB-Franco Acceptance of empty thing == not accepting anything! I think you are aware of "empty language", which means "no string", So to rephrase, "accepts empty string" == "accepts no string" == "does not accepts anything". If you still have problems, please comment.
– lU5er
Mar 17 '17 at 12:17
Thanks! - The fact you have explained in the above about DFA accepting empty string, can be related to what I have asked here: Why in a DFA the empty string distinguishes any accept state from any reject state?
– JB-Franco
Mar 17 '17 at 19:41
1
This answer is wrong because "accepts empty string" and "accepts no string" are not the same! The NFA with only one state and no transitions accepts no strings if the state is non-accepting, and the empty string (but no other strings) if the state is accepting. Similarly, a DFA can accept only the empty string and no others by having a start state which is accepting and then all transitions point to a non-accepting trap state like the one in this answer.
– Benjamin Cosman
May 29 '17 at 16:13
@BenjaminCosman, answer me one thing, what do you mean byempty string
?
– lU5er
May 30 '17 at 17:25
|
show 9 more comments
You've just said "accept empty string" and then "does not accept anything". Can you explain it better?
– JB-Franco
Mar 15 '17 at 22:24
1
@JB-Franco Acceptance of empty thing == not accepting anything! I think you are aware of "empty language", which means "no string", So to rephrase, "accepts empty string" == "accepts no string" == "does not accepts anything". If you still have problems, please comment.
– lU5er
Mar 17 '17 at 12:17
Thanks! - The fact you have explained in the above about DFA accepting empty string, can be related to what I have asked here: Why in a DFA the empty string distinguishes any accept state from any reject state?
– JB-Franco
Mar 17 '17 at 19:41
1
This answer is wrong because "accepts empty string" and "accepts no string" are not the same! The NFA with only one state and no transitions accepts no strings if the state is non-accepting, and the empty string (but no other strings) if the state is accepting. Similarly, a DFA can accept only the empty string and no others by having a start state which is accepting and then all transitions point to a non-accepting trap state like the one in this answer.
– Benjamin Cosman
May 29 '17 at 16:13
@BenjaminCosman, answer me one thing, what do you mean byempty string
?
– lU5er
May 30 '17 at 17:25
You've just said "accept empty string" and then "does not accept anything". Can you explain it better?
– JB-Franco
Mar 15 '17 at 22:24
You've just said "accept empty string" and then "does not accept anything". Can you explain it better?
– JB-Franco
Mar 15 '17 at 22:24
1
1
@JB-Franco Acceptance of empty thing == not accepting anything! I think you are aware of "empty language", which means "no string", So to rephrase, "accepts empty string" == "accepts no string" == "does not accepts anything". If you still have problems, please comment.
– lU5er
Mar 17 '17 at 12:17
@JB-Franco Acceptance of empty thing == not accepting anything! I think you are aware of "empty language", which means "no string", So to rephrase, "accepts empty string" == "accepts no string" == "does not accepts anything". If you still have problems, please comment.
– lU5er
Mar 17 '17 at 12:17
Thanks! - The fact you have explained in the above about DFA accepting empty string, can be related to what I have asked here: Why in a DFA the empty string distinguishes any accept state from any reject state?
– JB-Franco
Mar 17 '17 at 19:41
Thanks! - The fact you have explained in the above about DFA accepting empty string, can be related to what I have asked here: Why in a DFA the empty string distinguishes any accept state from any reject state?
– JB-Franco
Mar 17 '17 at 19:41
1
1
This answer is wrong because "accepts empty string" and "accepts no string" are not the same! The NFA with only one state and no transitions accepts no strings if the state is non-accepting, and the empty string (but no other strings) if the state is accepting. Similarly, a DFA can accept only the empty string and no others by having a start state which is accepting and then all transitions point to a non-accepting trap state like the one in this answer.
– Benjamin Cosman
May 29 '17 at 16:13
This answer is wrong because "accepts empty string" and "accepts no string" are not the same! The NFA with only one state and no transitions accepts no strings if the state is non-accepting, and the empty string (but no other strings) if the state is accepting. Similarly, a DFA can accept only the empty string and no others by having a start state which is accepting and then all transitions point to a non-accepting trap state like the one in this answer.
– Benjamin Cosman
May 29 '17 at 16:13
@BenjaminCosman, answer me one thing, what do you mean by
empty string
?– lU5er
May 30 '17 at 17:25
@BenjaminCosman, answer me one thing, what do you mean by
empty string
?– lU5er
May 30 '17 at 17:25
|
show 9 more comments
Thanks for contributing an answer to Mathematics Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Some of your past answers have not been well-received, and you're in danger of being blocked from answering.
Please pay close attention to the following guidance:
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f341124%2ffinite-automaton-that-recognizes-the-empty-language-emptyset%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Write "This automaton is...." or "These automata are....". (I fixed this in the question.)
– Michael Hardy
Mar 26 '13 at 3:24