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#26 Re: Jokes » identities » 2005-12-27 22:46:33

Ahah cool
Like

Linux=(Windows - (∑(i=1,+∞)Bug(i) - My$$$ ) ) + Happiness^2

#27 Re: Help Me ! » derivative of an exponential function » 2005-12-27 22:34:46

5          x
f(x)= x     •   3

                4       x            5
ƒ¹(x)= 5x    •  3      +   x     •  xln3

And for this:
               0.7x
y=(cosx)
I dunno if u have to calculate the derivative, but u can rewrite it in this way
         
           (7/10)x • ln(cosx)
f(x)= e

#28 Re: Help Me ! » Very interesting problems.. » 2005-12-27 04:39:04

no..Not the smallest solution..the smallest n

#29 Re: Help Me ! » Very interesting problems.. » 2005-12-26 23:01:10

O H    M Y   G O D.
I think tat Santa Claus has stolen my brain!!!!!!! For SURE!

ok ok ok ok... ONLY THE LAST NUMBER OF THE CHAIN OR OF THE SEQUENCE MUST BE SUM WITH THE FIRST NUMBER AND THEM HAVE TO BE A PERFECT SQUARE!!!  [sorry again..]

so any lists it's ok,       

LAST RIGHT EXAMPLE:
Let a..z  be numbers:
a  b  c d  e f g h i

a+b=perfect square      b+c=perfect square    c+d=perfect square  d+e=perfect square  e+f=perfect square
f+g=perfect square       g+h=perfect square   h+i perfect square         ANDD      i+a= perfect square!!

A THING LIKE THIS. SORRY FOR ALL MY MISTAKES!!
So it's important tat the sum of 2 consecutive numbers it's always a perfect square and the last with the first have to be a perfect square yet! [to complete the circular sequence]
-And it's not important tat all numbers are present.
THE ONLY 2 THINGS ARE:
- Which is this n which u can arrange  a..b..z..k...to n in a circular sequence
-The longest list that u can make with this n.
TIP:
This minimum n is less than 50.  I think we need to make a circular sequence with all the combinations from 1 since 50  [except 0...in fact n>1]

Thank u again.
Forgive me!

#30 Re: Help Me ! » Very interesting problems.. » 2005-12-26 10:25:40

1 15 10 6 3 
This is the correct sequence written by my teacher!
SO we need to look for n from 15 !!  so we can think tat this n   is   15<n<50....mumble...

#31 Re: Help Me ! » Very interesting problems.. » 2005-12-26 10:23:28

ricky I tried to write the correct version of the question. I think that krass is doing well.
This n is the minimum integer tat allow u to arrange all the numbers  [1.2.4..till this n] in a circular sequence and the sum of 2 consecutive numbers is always a perfect square , but please read my last post.
And the tip was tat this minimum integer n is less than 50. so we need to look for this n as krassi is doing.
I think u wrote n<>9 coz u trying to arrange all the numbers till 9 right? so u wrote <> coz 9 isn't the minimum numbeR? good!
There is only n.

#32 Re: Help Me ! » Very interesting problems.. » 2005-12-24 23:01:38

I'm a fu**in stupid!! I didn't see well the list written in old posts..Sorry me. These holidays are making me stupid!

1 24 is right coz 1+24 is 25 ok..

1 24 12 isn't right coz  24+12=36 ok perfect square but  12+1=13 isn't a perfect square!!!

1 24 12 4  isn't right.  12+4 is  perfect square but  4+1=5 isn't a perfect square.

All have to work in  a circular sequence too.  The last number of the list + the first number = perfect square too!!

a  little right sequence is:

1 15 10 6 3       1+15   15+10  10+6  6+3    AND  3+1  all perfect squares!

But it isn't enough to explain which is the minimun n to arrange all the entire numbers from 1 to this n in a circular sequence. [as first question]
As second question is to write a sequence longer than that above one.

Sorry me again!

PS: THE TIP is that this minimum n is less than 50. So we need to find a circular sequence made with all number from 1 to this  minimum n.  (n<50)

HAPPY XMAS TO ALL

#33 Re: Help Me ! » Very interesting problems.. » 2005-12-24 06:58:50

Sorry mathsyperson! Yesterday it was too late and I was so confused
About the problem..I making some mistakes neutral...You started well
The only 2 things to do are:
1)Choose a n (entire). Try to arrange in a circulare sequence all the numbers from 1 to n. (1,2,3,4,...,n)
  Check if the sum of 2 consecutive numbers is always a perfect square. Which is the smallest n in which u can do  that?
the tip is:  this n is less than 50..so  n<50.

2) Write a sequence (like the example)


Sorry for my  mistakes. I think now it's ok.

#34 Re: Help Me ! » Very interesting problems.. » 2005-12-23 13:17:23

krassi_holmz wrote:

But wait a minute...
If i've understood correctly
N cant be greater than n so some numbers may be repeated.

No no. No numbers can be repeated!
I read that this N>1  is less than 50

So you have to combine all the numbers from 1 to 50 without repeat a same number twice.

#35 Re: Help Me ! » Very interesting problems.. » 2005-12-23 13:13:05

sorry!! I wrong in the first post
a)"FOR WHICH ENTIRES  N>1 is possible ARRANGE IN A CERTAIN WAY ALL THE ENTIRE NUMBERS 1,2,3...,n AROUND A CIRCLE (CIRCULAR SEQUENCE),THAT THE SUM OF 2 CONSECUTIVE NUMBERS IS ALWAYS A PERFECT SQUARE."?
b) and then WHICH IS THE SMALLEST ENTIRE NUMBER  N>1 FOR WHICH IS POSSIBLE TO FIND THIS CIRCULAR SEQUENCE?

But your last example was ok!
EXAMPLE: 1 24 12 4 5 11 14 2 7 9 27 22 3 .........

#36 Re: Help Me ! » Very interesting problems.. » 2005-12-23 12:50:57

No no n is the set of integer numbers from n>1
n could be  whatever integer number! It's not the lenght of the circular sequence.
The problem is find for which integers n u can arrange all the natural numbers [from 1 to N eg. 1,2,3...N] in a circular sequence.
In the last right example  this set of integer numbers  was : 1, 24,12,4,5 etc..

#37 Re: Help Me ! » Very interesting problems.. » 2005-12-23 12:23:45

krassi_holmz wrote:

And here's ss with 13 numbers:
1 24 12 4 5 11 14 2 7 9 27 22 3!

Yes! Right!! That way!
This problem is very nice but it's not easy neutral


However thanx to all!!!!

#38 Re: Help Me ! » Very interesting problems.. » 2005-12-23 11:10:10

I read another info. This integer n>1  is less than 50!! mh...
so  n is        1<n<50.. Now the problem is to look for the exact value!

#39 Re: Help Me ! » Very interesting problems.. » 2005-12-23 11:07:43

&& stands for the logic AND

For example a right circular sequence could be this:


1 15 10 6 3          1+15=16 perfect square    15+10=25 perfect square ...till 3 +1 (the first number) is a perfect square
I was also lookin for a program in whatever language..

#40 Re: Help Me ! » Very interesting problems.. » 2005-12-23 01:47:32

Please...help me! tongue

Waiting for ur help

Happy Holidays

#41 Re: Help Me ! » Is there any way to solve this algebraically? » 2005-12-22 04:55:14

Hi.
I tried a thing like this  (but I think that it's the same thing)
Let ln log base e
2^x=2x
ln(2^x)=ln2+lnx
xln2=ln2+lnx
x=1+ln(x)/ln(2)
and so

x=1+Log    (x)
               2

#42 Help Me ! » Very interesting problems.. » 2005-12-21 05:22:54

seerj
Replies: 166

Hi all i'm new in this forum! [ And Happy Xmas Holidays!]
I should solve a problem and I think that it's not so difficult but I don't know where starts.
The problem is:
For which integer n >1 it is possible to arrange all the entire numbers from 1 to n around a circle so that the sum of two consecutive numbers is always a perfect square?
[and..]
Which is the smallest integer n>1 for which it is possible to find this circular sequence?

Thanks 2 all in advance!!

SeerJ

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