How many ways to place identical boxes in a row?
up vote
0
down vote
favorite
How many ways there are to arrange ten (or n) identical boxes in a row of ten (or n) places when stacking is allowed? I guess you need to find how many different arrays there are but how?
combinatorics
add a comment |
up vote
0
down vote
favorite
How many ways there are to arrange ten (or n) identical boxes in a row of ten (or n) places when stacking is allowed? I guess you need to find how many different arrays there are but how?
combinatorics
1
If you consider the height of stack $j$ as $x_j$, then you're looking at the equation $$ x_1 + x_2 + x_3 + x_4 + ldots + x_{10} = n $$ The number of solutions can be found with the "stars and bars" method.
– Matti P.
Nov 15 at 11:21
This is an example of a composition problem.
– N. F. Taussig
Nov 15 at 17:13
Thanks a bunch. I was quite sure this was some classical problem but just couldn't figure it out myself
– user2566933
Nov 16 at 19:51
add a comment |
up vote
0
down vote
favorite
up vote
0
down vote
favorite
How many ways there are to arrange ten (or n) identical boxes in a row of ten (or n) places when stacking is allowed? I guess you need to find how many different arrays there are but how?
combinatorics
How many ways there are to arrange ten (or n) identical boxes in a row of ten (or n) places when stacking is allowed? I guess you need to find how many different arrays there are but how?
combinatorics
combinatorics
asked Nov 15 at 11:17
user2566933
62
62
1
If you consider the height of stack $j$ as $x_j$, then you're looking at the equation $$ x_1 + x_2 + x_3 + x_4 + ldots + x_{10} = n $$ The number of solutions can be found with the "stars and bars" method.
– Matti P.
Nov 15 at 11:21
This is an example of a composition problem.
– N. F. Taussig
Nov 15 at 17:13
Thanks a bunch. I was quite sure this was some classical problem but just couldn't figure it out myself
– user2566933
Nov 16 at 19:51
add a comment |
1
If you consider the height of stack $j$ as $x_j$, then you're looking at the equation $$ x_1 + x_2 + x_3 + x_4 + ldots + x_{10} = n $$ The number of solutions can be found with the "stars and bars" method.
– Matti P.
Nov 15 at 11:21
This is an example of a composition problem.
– N. F. Taussig
Nov 15 at 17:13
Thanks a bunch. I was quite sure this was some classical problem but just couldn't figure it out myself
– user2566933
Nov 16 at 19:51
1
1
If you consider the height of stack $j$ as $x_j$, then you're looking at the equation $$ x_1 + x_2 + x_3 + x_4 + ldots + x_{10} = n $$ The number of solutions can be found with the "stars and bars" method.
– Matti P.
Nov 15 at 11:21
If you consider the height of stack $j$ as $x_j$, then you're looking at the equation $$ x_1 + x_2 + x_3 + x_4 + ldots + x_{10} = n $$ The number of solutions can be found with the "stars and bars" method.
– Matti P.
Nov 15 at 11:21
This is an example of a composition problem.
– N. F. Taussig
Nov 15 at 17:13
This is an example of a composition problem.
– N. F. Taussig
Nov 15 at 17:13
Thanks a bunch. I was quite sure this was some classical problem but just couldn't figure it out myself
– user2566933
Nov 16 at 19:51
Thanks a bunch. I was quite sure this was some classical problem but just couldn't figure it out myself
– user2566933
Nov 16 at 19:51
add a comment |
1 Answer
1
active
oldest
votes
up vote
2
down vote
Arrange the $n$ boxes in a row, like so:
$$square square square square square square square square square square square square ldots square square square square tag{1}$$
There are $n-1$ spaces in between. "Stacking" the boxes means inserting a $|$ into some of the spaces in $(1)$, indicating when a new stack shall begin. Since there are $2^{n-1}$ ways to choose a subset of the $n-1$ spaces there are $2^{n-1}$ ways to arrange the boxes in a row of nonempty stacks.
add a comment |
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
2
down vote
Arrange the $n$ boxes in a row, like so:
$$square square square square square square square square square square square square ldots square square square square tag{1}$$
There are $n-1$ spaces in between. "Stacking" the boxes means inserting a $|$ into some of the spaces in $(1)$, indicating when a new stack shall begin. Since there are $2^{n-1}$ ways to choose a subset of the $n-1$ spaces there are $2^{n-1}$ ways to arrange the boxes in a row of nonempty stacks.
add a comment |
up vote
2
down vote
Arrange the $n$ boxes in a row, like so:
$$square square square square square square square square square square square square ldots square square square square tag{1}$$
There are $n-1$ spaces in between. "Stacking" the boxes means inserting a $|$ into some of the spaces in $(1)$, indicating when a new stack shall begin. Since there are $2^{n-1}$ ways to choose a subset of the $n-1$ spaces there are $2^{n-1}$ ways to arrange the boxes in a row of nonempty stacks.
add a comment |
up vote
2
down vote
up vote
2
down vote
Arrange the $n$ boxes in a row, like so:
$$square square square square square square square square square square square square ldots square square square square tag{1}$$
There are $n-1$ spaces in between. "Stacking" the boxes means inserting a $|$ into some of the spaces in $(1)$, indicating when a new stack shall begin. Since there are $2^{n-1}$ ways to choose a subset of the $n-1$ spaces there are $2^{n-1}$ ways to arrange the boxes in a row of nonempty stacks.
Arrange the $n$ boxes in a row, like so:
$$square square square square square square square square square square square square ldots square square square square tag{1}$$
There are $n-1$ spaces in between. "Stacking" the boxes means inserting a $|$ into some of the spaces in $(1)$, indicating when a new stack shall begin. Since there are $2^{n-1}$ ways to choose a subset of the $n-1$ spaces there are $2^{n-1}$ ways to arrange the boxes in a row of nonempty stacks.
answered Nov 15 at 14:00
Christian Blatter
170k7111324
170k7111324
add a comment |
add a comment |
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%2f2999558%2fhow-many-ways-to-place-identical-boxes-in-a-row%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
1
If you consider the height of stack $j$ as $x_j$, then you're looking at the equation $$ x_1 + x_2 + x_3 + x_4 + ldots + x_{10} = n $$ The number of solutions can be found with the "stars and bars" method.
– Matti P.
Nov 15 at 11:21
This is an example of a composition problem.
– N. F. Taussig
Nov 15 at 17:13
Thanks a bunch. I was quite sure this was some classical problem but just couldn't figure it out myself
– user2566933
Nov 16 at 19:51