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Topic: Help with creating a function
Replies: 12   Last Post: Nov 19, 2013 3:48 AM

 Messages: [ Previous | Next ]
 Robert Crandal Posts: 3 Registered: 11/18/13
Re: Help with creating a FORMULA. (no abs value)
Posted: Nov 18, 2013 5:51 AM

"quasi" <quasi@null.set> wrote:
>
> The function f defined on the set of nonnegative integers
> by the formula
>
> f(x) = ((x-1)*(((2*x-1)/abs(2*x-1))+1)/2)+1
>

quasi,

Thanks, that's awesome . I dunno how you whipped
that out so fast, but I won't ask. 8)

Here's a tougher example:

Suppose I have this data:

X Y
-- --
0 -1
1 1
2 1
3 1
. .
N N

(Assume X is an integer >= zero)

Is there a formula for this set of non-negative
integers that does NOT use the absolute value
function? I thought maybe an alternating series
would help here, but I can't think of anything.

Any ideas?

Date Subject Author
11/18/13 Robert Crandal
11/18/13 quasi
11/18/13 Robert Crandal
11/18/13 quasi
11/18/13 David Hartley
11/18/13 quasi
11/18/13 Roland Franzius
11/18/13 quasi
11/18/13 quasi
11/19/13 quasi
11/18/13 Richard Tobin
11/18/13 Stuart M Newberger
11/18/13 Peter Percival