Mixing
How many strings of length $4$ can be built from letters $a, b, c, d, e$?
1
$begingroup$
$B$ is a group of all strings of length $4$ built using letters $a,b,c,d,e$.
What is $|B|$?
I think the answer is $5^4$, but why we don't need to consider the duplicate letters here?
combinatorics discrete-mathematics
edited Jan 23 at 12:17
N. F. Taussig
44.6k103357
asked Jan 22 at 18:21
user3523226user3523226
607
$endgroup$
add a comment |
1
$begingroup$
$B$ is a group of all strings of length $4$ built using letters $a,b,c,d,e$.
What is $|B|$?
I think the answer is $5^4$, but why we don't need to consider the duplicate letters here?
combinatorics discrete-mathematics
edited Jan 23 at 12:17
N. F. Taussig
44.6k103357
asked Jan 22 at 18:21
user3523226user3523226
607
$endgroup$
4
$begingroup$
In a mathematics site, you should be careful using the word "group." Your question has nothing whatsoever to do with groups.
$endgroup$
– David G. Stork
Jan 22 at 18:22
3
$begingroup$
$5^4$ is correct if you allow duplicate letters. If you insist on no duplicates then it is $5times 4times 3times 2$. Usually when one speaks of "all strings", duplicates are allowed.
$endgroup$
– lulu
Jan 22 at 18:26
$begingroup$
You should say that $B$ is the set of all strings of length $4$ built using letters $a, b, c, d, e$.
$endgroup$
– N. F. Taussig
Jan 23 at 12:18
add a comment |
1
1
1
$begingroup$
$B$ is a group of all strings of length $4$ built using letters $a,b,c,d,e$.
What is $|B|$?
I think the answer is $5^4$, but why we don't need to consider the duplicate letters here?
combinatorics discrete-mathematics
edited Jan 23 at 12:17
N. F. Taussig
44.6k103357
asked Jan 22 at 18:21
user3523226user3523226
607
$endgroup$
$B$ is a group of all strings of length $4$ built using letters $a,b,c,d,e$.
What is $|B|$?
I think the answer is $5^4$, but why we don't need to consider the duplicate letters here?
combinatorics discrete-mathematics
combinatorics discrete-mathematics
edited Jan 23 at 12:17
N. F. Taussig
44.6k103357
asked Jan 22 at 18:21
user3523226user3523226
607
edited Jan 23 at 12:17
N. F. Taussig
44.6k103357
asked Jan 22 at 18:21
user3523226user3523226
607
edited Jan 23 at 12:17
N. F. Taussig
44.6k103357
edited Jan 23 at 12:17
N. F. Taussig
44.6k103357
edited Jan 23 at 12:17
N. F. Taussig
44.6k103357
44.6k103357
asked Jan 22 at 18:21
user3523226user3523226
607
asked Jan 22 at 18:21
user3523226user3523226
607
asked Jan 22 at 18:21
user3523226user3523226
607
607
4
$begingroup$
In a mathematics site, you should be careful using the word "group." Your question has nothing whatsoever to do with groups.
$endgroup$
– David G. Stork
Jan 22 at 18:22
3
$begingroup$
$5^4$ is correct if you allow duplicate letters. If you insist on no duplicates then it is $5times 4times 3times 2$. Usually when one speaks of "all strings", duplicates are allowed.
$endgroup$
– lulu
Jan 22 at 18:26
$begingroup$
You should say that $B$ is the set of all strings of length $4$ built using letters $a, b, c, d, e$.
$endgroup$
– N. F. Taussig
Jan 23 at 12:18
add a comment |
4
$begingroup$
In a mathematics site, you should be careful using the word "group." Your question has nothing whatsoever to do with groups.
$endgroup$
– David G. Stork
Jan 22 at 18:22
3
$begingroup$
$5^4$ is correct if you allow duplicate letters. If you insist on no duplicates then it is $5times 4times 3times 2$. Usually when one speaks of "all strings", duplicates are allowed.
$endgroup$
– lulu
Jan 22 at 18:26
$begingroup$
You should say that $B$ is the set of all strings of length $4$ built using letters $a, b, c, d, e$.
$endgroup$
– N. F. Taussig
Jan 23 at 12:18
4
4
$begingroup$
In a mathematics site, you should be careful using the word "group." Your question has nothing whatsoever to do with groups.
$endgroup$
– David G. Stork
Jan 22 at 18:22
$begingroup$
In a mathematics site, you should be careful using the word "group." Your question has nothing whatsoever to do with groups.
$endgroup$
– David G. Stork
Jan 22 at 18:22
3
3
$begingroup$
$5^4$ is correct if you allow duplicate letters. If you insist on no duplicates then it is $5times 4times 3times 2$. Usually when one speaks of "all strings", duplicates are allowed.
$endgroup$
– lulu
Jan 22 at 18:26
$begingroup$
$5^4$ is correct if you allow duplicate letters. If you insist on no duplicates then it is $5times 4times 3times 2$. Usually when one speaks of "all strings", duplicates are allowed.
$endgroup$
– lulu
Jan 22 at 18:26
$begingroup$
You should say that $B$ is the set of all strings of length $4$ built using letters $a, b, c, d, e$.
$endgroup$
– N. F. Taussig
Jan 23 at 12:18
$begingroup$
You should say that $B$ is the set of all strings of length $4$ built using letters $a, b, c, d, e$.
$endgroup$
– N. F. Taussig
Jan 23 at 12:18
add a comment |
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4
$begingroup$
In a mathematics site, you should be careful using the word "group." Your question has nothing whatsoever to do with groups.
$endgroup$
– David G. Stork
Jan 22 at 18:22
3
$begingroup$
$5^4$ is correct if you allow duplicate letters. If you insist on no duplicates then it is $5times 4times 3times 2$. Usually when one speaks of "all strings", duplicates are allowed.
$endgroup$
– lulu
Jan 22 at 18:26
$begingroup$
You should say that $B$ is the set of all strings of length $4$ built using letters $a, b, c, d, e$.
$endgroup$
– N. F. Taussig
Jan 23 at 12:18