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#26 2013-10-14 19:30:55

anonimnystefy
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Re: no. of path in Grid

bobbym wrote:

There is another more general way. That maybe can answer for many missing intersections.

I like your first method. It is easily programmable.


The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

#27 2013-10-14 19:33:45

bobbym
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Re: no. of path in Grid

You mean labeling the vertices with the sums?


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#28 2013-10-14 19:36:12

anonimnystefy
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Re: no. of path in Grid

Yep. DP is really nice.


The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

#29 2013-10-14 19:42:25

bobbym
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Re: no. of path in Grid

But there is a much nicer way that is probably quicker too!


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#30 2013-10-14 19:50:53

anonimnystefy
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Re: no. of path in Grid

Which is?


The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

#31 2013-10-14 20:03:37

bobbym
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Re: no. of path in Grid

I am being called away so I will show the method as soon as I get back.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#32 2013-10-14 20:08:54

anonimnystefy
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Re: no. of path in Grid

Okay, no hurry. And if they threaten you, just ask yourself WWHD?


The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

#33 2013-10-14 22:58:50

bobbym
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Re: no. of path in Grid

WWHD? Why Would Hay Decompose?




Now run

MatrixPower[A, 8][[1]]

the last entry means from 1 to 24, 38 ways.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#34 2013-10-15 02:26:05

anonimnystefy
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Re: no. of path in Grid

It takes much londer if you have a larger grid. I'd say DP is better here.

WWHD - What Would Hulk Do?


The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

#35 2013-10-15 09:55:47

bobbym
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Re: no. of path in Grid

The matrix can be filled by a program as the "Dice" guy does. Also it is a lot easier for a computer to do.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#36 2013-10-15 10:16:12

anonimnystefy
Real Member

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Re: no. of path in Grid

I'm not sure if getting the 8th piwer if a huge matrix is fast.


The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

#37 2013-10-15 10:17:35

bobbym
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Re: no. of path in Grid

Hohohohohohohoo! That is a good one! I just talked to Mathematica and he said it sure is. Also there are ways to just get one element of that matrix!


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#38 2013-10-16 03:33:48

anonimnystefy
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Re: no. of path in Grid

What if you had a grid 100 by 100. You would need to get th 100th power of a 10201 by 10201 matrix!

Last edited by anonimnystefy (2013-10-16 03:33:59)


The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

#39 2013-10-16 12:37:45

bobbym
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Re: no. of path in Grid

You would not!


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#40 2013-10-16 19:45:52

anonimnystefy
Real Member

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Re: no. of path in Grid

Then what?


The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

#41 2013-10-16 19:47:05

bobbym
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Re: no. of path in Grid

There is an interesting little idea in Computer math that might help.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#42 2013-10-16 19:58:30

anonimnystefy
Real Member

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Re: no. of path in Grid

Diagonalization?


The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

#43 2013-10-16 20:12:43

bobbym
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Re: no. of path in Grid

Matrix moves is the one.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#44 2013-10-17 06:47:30

anonimnystefy
Real Member

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Re: no. of path in Grid

I'd say that's the same thing I said.


The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

#45 2013-10-17 06:49:02

bobbym
Administrator

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Re: no. of path in Grid

About what?


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

#46 2013-10-17 09:07:40

anonimnystefy
Real Member

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Re: no. of path in Grid

I meant to say that I think me were thinking about the sane thing in posts #42 and #43.


The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

#47 2013-10-17 13:00:12

bobbym
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Re: no. of path in Grid

Then that is proof of ESP.

Were you also thinking about a big corned beef sandwich? No? Neither was I! Another amazing coincidence or...


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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