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#1 Re: This is Cool » seven and thirteen » 2009-06-14 00:37:05

For bobbym
Quote:

http://en.wikipedia.org/wiki/Happy_number

RickIsAnIdiot

Thanks bobbym! keep up the good work..

#2 Re: This is Cool » Domestos Kills Germs! » 2009-06-14 00:34:29

For simron
Quote:

Also:
1-.9=.1
1-.99=.01
1-.999=.001
limit as x goes to infinity (1-x(.1+.01+.001+.0001...))=0
limit as x goes to infinity (x(.1+.01+.001+.0001...))=1
SO THE LIMIT OF .99999... IS 1
Q.E.D.
I think I know where Anthony is coming from. Infinity is kind of a hard concept for everyone (well... me for sure. It sure took me a while for me to figure it out).

RickIsAnIdiot

There is  NO LIMIT OF .99999... AS 1 ( To Limit  .9999... is to Stop the .9's being continuous!...as soon as you make a Limit it will be
contradictory!

#3 Re: This is Cool » FLT DEMONSTRATION By Anthony.R.Brown » 2009-06-14 00:25:38

For simron
Quote:

1)What else does pi equal?
2).33...

RickIsAnIdiot

Pi / Pi = 1

#4 Re: This is Cool » seven and thirteen » 2009-06-13 02:59:52

Happy numbers are related to a sequence where each term is determined by the sum of the squares of the previous term's digits. eg.

7
49 (= 7²)
97 (= 4² + 9²)
130
10
1
1
1
...
For mathsyperson
Quote:

A happy number is a number that initiates a sequence that goes to 1, like 7 does above.

An unhappy number will instead eventually fall into the following loop:
4, 16, 37, 58, 89, 145, 42, 20, 4...

RickIsAnIdiot

Do you have any more Happy Number examples.

#5 Re: This is Cool » Prime Numbers!!! » 2009-06-13 02:56:33

For Avon
Quote:

I think bobbym's point is that, even for computers, the calculation of large factorials is not a very good way of testing if numbers are prime.

At university, if I type Factorization(1111111111111111111); into Magma I can't even tell that there is a delay before it prints [ <1111111111111111111, 1> ] confirming that 1111111111111111111 is indeed a prime.

If I type Factorial(1111111111111111111); instead it refuses to do the calculation because 1111111111111111111 is too large.

RickIsAnIdiot

Can you type Factorization(1111111111111111111); into Magma ? And it shows all the digit,s ?

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