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#1 2007-01-15 05:19:57

dreamcradle
Guest

this might be easy but i can't do it... (sorry not good at math)

I want to make all possible combinations with this 5 chars:
1, 3, 4, 0, @

like:
1
3
4
0
@
1,3
1,4
1,0
1,@
......
........

1,3,4,0,@

can anyone help me? Thanks in advance...

#2 2007-01-15 05:23:28

dreamcradle
Guest

Re: this might be easy but i can't do it... (sorry not good at math)

sorry forget to mention the following:

where

1,3 = 3,1

as so as...

1,3,0 = 3,0,1

so the char position doesn't matter...

#3 2007-01-15 05:36:50

dreamcradle
Guest

Re: this might be easy but i can't do it... (sorry not good at math)

hmm i think i got them... but not sure...

{1} {3} {4} {0} {@}
{1,3} {1,4} {1,0} {1,@} {3,4} {3,0} {3,@} {4,0} {4,@} {0,@}
{1,3,4} {1,3,0} {1,3,@} {1,4,0} {1,4,@} {1,0,@} {3,4,0} {3,4,@} {3,0,@} {4,0,@}
{1,3,4,0} {1,3,4,@} {1,3,0,@} {1,4,0,@} {3,4,0,@}
{1,3,4,0,@}

#4 2007-01-15 07:16:44

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

Re: this might be easy but i can't do it... (sorry not good at math)

Yes, that's them all. Unless you count the empty set {} as another combination, in which case that's one more.

Depending on whether you do or not, the total is either 32 or 31.


Why did the vector cross the road?
It wanted to be normal.

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#5 2007-01-15 08:40:57

MathsIsFun
Administrator
Registered: 2005-01-21
Posts: 7,711

Re: this might be easy but i can't do it... (sorry not good at math)

That is called the Power Set and we even have a Power Set Maker which gives:

{}, {1}, {3}, {1,3}, {4}, {1,4}, {3,4}, {1,3,4}, {0}, {1,0}, {3,0}, {1,3,0}, {4,0}, {1,4,0}, {3,4,0}, {1,3,4,0}, {@}, {1,@}, {3,@}, {1,3,@}, {4,@}, {1,4,@}, {3,4,@}, {1,3,4,@}, {0,@}, {1,0,@}, {3,0,@}, {1,3,0,@}, {4,0,@}, {1,4,0,@}, {3,4,0,@}, {1,3,4,0,@}


"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

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#6 2007-01-15 08:58:21

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

Re: this might be easy but i can't do it... (sorry not good at math)

Wow, I never saw that page before. Either that or I forgot it, but probably the first because I wouldn't forget a page as good as that! The automated set maker is very good as well. Top-notch work!


Why did the vector cross the road?
It wanted to be normal.

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