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#1951 2012-12-12 10:31:24

anonimnystefy
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Re: What do you think?

Out of my head.


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1952 2012-12-12 10:34:06

bobbym
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Re: What do you think?

That is very good. It is a nice problem. Actually the answer is not that hard.


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1953 2012-12-12 10:35:21

anonimnystefy
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Re: What do you think?

What do you get for 3x3 unit squares?


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1954 2012-12-12 10:38:40

bobbym
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From: Bumpkinland
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Re: What do you think?

Hi;


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1955 2012-12-12 10:45:43

anonimnystefy
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From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: What do you think?

That is not correct.


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1956 2012-12-12 10:49:27

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,615

Re: What do you think?

What do you get?


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1957 2012-12-12 10:51:47

anonimnystefy
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From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: What do you think?

433.

I think you have misuderstood the problem. Rea it once again.


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1958 2012-12-12 10:54:18

bobbym
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From: Bumpkinland
Registered: 2009-04-12
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Re: What do you think?

Hi;

I was going to say the same thing. Post your method and maybe we can resolve this.


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1959 2012-12-12 10:56:38

anonimnystefy
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From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: What do you think?

I did it by counting all possibilities.

The thing is that, if a squares neighbour is a 0, the square itself must be either 0 or 1. Your counting method allows the squares to be greater than 1 even if neighbours are 0.


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1960 2012-12-12 10:59:52

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,615

Re: What do you think?

Hi;

Give me a chance to show why I think my method is correct. I will post a diagram.


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1961 2012-12-12 11:02:41

anonimnystefy
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Registered: 2011-05-23
Posts: 15,657

Re: What do you think?

Sure!


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1962 2012-12-12 11:07:38

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,615

Re: What do you think?

Here is the possibilities for each box.

View Image: 2012-12-12_150444.gif

In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1963 2012-12-12 11:13:56

anonimnystefy
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From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: What do you think?

That is not correct. The top left-hand side box can contain a 2 only if both its neighbours are 1s. Other wise it can take values of 0 and 1 only.


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1964 2012-12-12 11:23:24

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,615

Re: What do you think?

Hi;

Yes, I know. But that still means 3 choices for that box. The multiplication takes care of what is the next boxes.


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1965 2012-12-12 11:26:00

anonimnystefy
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From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: What do you think?

Your method allows the square to be filled like this:

2 0 2
0 0 0
2 0 2
which is not allowed by the problem!


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1966 2012-12-12 11:31:20

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,615

Re: What do you think?

Hi;

I do not think so, I worked from the inside out. I will try to enumerate all of them. You may be right.


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1967 2012-12-12 11:38:08

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: What do you think?

My answer might not be correct, but I am sure that the one in #1954 isn't correct.


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1968 2012-12-12 19:55:51

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,615

Re: What do you think?

Hi;

You are correct with the answer of 433 for a 3 x 3. Very good!


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1969 2012-12-12 21:04:07

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: What do you think?

Unfortunately, the problem is harder this way!


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1970 2012-12-12 21:09:44

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,615

Re: What do you think?

Well young fella, are you going to explain your method?


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1971 2012-12-12 21:12:34

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: What do you think?

I did it by casework, the cases being tje possibilities for the squares around the center square.

Unfortunately, it cannot be applied to the 5x5...


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1972 2012-12-12 21:20:07

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,615

Re: What do you think?

Hi;

The approach I used is maybe possible with the 5 x 5 but certainly not for an 11 x 11.


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1973 2012-12-12 21:21:21

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: What do you think?

Which approach is that?


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1974 2012-12-12 21:25:54

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 90,615

Re: What do you think?

Experimental of course!

How many times have even weak programmers solved problems when mathematicians just went, "Duh?"


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1975 2012-12-12 21:29:08

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: What do you think?

How did you count all the possibilities?


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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