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#28 Re: Help Me ! » Limit » 2012-11-20 04:50:36

Hi;

L'Hopital's rule is the best way.

#29 Re: This is Cool » Pascal's square » 2012-11-12 20:33:37

Hi;

You're absolutely right.

#30 Re: This is Cool » Pascal's square » 2012-11-12 05:05:56

Hi bobbym;

Excellent! After a lot of work we arrived to a conclusion. Good job!

#31 Re: This is Cool » Pascal's square » 2012-11-12 03:18:08

Hi;

I agree with you, but I've got some difficults regarding what you're try to prove. The formula is hard to find.

#32 Re: This is Cool » Pascal's square » 2012-11-12 01:52:57

Hi bobbym;

I wanted to ask only if my formula was correct or incorrect. Then I tried to prove a different thing. I'm still thinking about what you're trying to prove. My formula was a separate thing.

#33 Re: This is Cool » Pascal's square » 2012-11-11 21:35:55

Hi;

If we take a diagonal of the square:
8 4 4 4 8
Then we trasform the numbers in exponents of 2
2^3 2^2 2^2 2^2 2^3
The exponent of the first term (in this case 3) is the number of the exponents of 2 between the first and the last term. So we can say that 2^n*2 for the first and the last term, then, since that the exponents of 2 between the first and the last term are the half of the first term, so (2^n/2) multiplied by the exponent of the frist term (in this case n), so (2^n/2)*n. Then we add (2^n/2)*n to 2^n*2. The result is the sum of the numbers of each diagonal. The complete formula is  2^n*2 + (2^n/2)*n that we can write it also like 2^(n+1)*n+2^(n-1). This formula is valid for all the diagonals, except for the first one.

#34 Re: This is Cool » Pascal's square » 2012-11-11 17:55:25

Hi;

Ok, but why this formula  2^(n-1)*n + 2^(n+1) is incorrect?

#35 Re: This is Cool » Pascal's square » 2012-11-11 09:50:06

Hi bobbym;

Why do we need two formulas to obtain the table?

#37 Re: This is Cool » Pascal's square » 2012-11-10 22:20:35

Hi bobbym;

Good job! Can I see the expression?

#38 Re: This is Cool » Pascal's square » 2012-11-10 11:10:57

Hi;

Ok. Keep me informed, thanks.

#40 Re: This is Cool » Pascal's square » 2012-11-10 00:00:11

Hi;

So what do you suggest?

#42 Re: This is Cool » Pascal's square » 2012-11-09 21:05:55

Hi everyone;

I tried to find a formula to obtain the sum of the numbers of each diagonal and this is the result:

(2^n)*2+(2^n)2*n, then I simplified it and I obtained 2^(n-1)*n + 2^(n+1). The result is Number of 1's in all compositions of n+1 (A045623 of OEIS), because 2^(n-1)*n + 2^(n+1. Generate the same terms of (n+3)*2^(n-2), the formula of A045623, proposed by anonimnystefy.

#43 Re: This is Cool » Pascal's square » 2012-11-05 02:40:23

Hi anonmystefy;

I agree with you.

#44 Re: This is Cool » Pascal's square » 2012-11-05 02:38:20

Hi bobbym;

Thanks for compliment.

#45 Re: This is Cool » Pascal's square » 2012-11-05 02:24:53

Hi;

Now I understand. Thanks!

#46 Re: This is Cool » Pascal's square » 2012-11-05 02:16:28

Hi;

Sorry, but I don't understand what you mean when you say "Does seem to be generating the compositions.

#48 Re: This is Cool » Pascal's square » 2012-11-04 09:52:01

Hi bobbym;

So what are your conclusions?

#49 Re: This is Cool » Pascal's square » 2012-11-03 10:58:45

Ok. Let me know if you find something interesting.

#50 Re: This is Cool » Pascal's square » 2012-11-03 10:10:07

At least we find an alternative system to obtain square array of Delannoy numbers!

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