# Re: Question on modular algebra

*From*: "Dani Camps" <danicamps81@xxxxxxxxx>*Date*: 16 Mar 2007 02:59:27 -0700

On 16 mar, 10:54, "Dani Camps" <danicamp...@xxxxxxxxx> wrote:

On 15 mar, 16:46, Peter Pearson <ppear...@xxxxxxxxxxxxxxx> wrote:

On 14 Mar 2007 08:43:26 -0700, Dani Camps <danicamp...@xxxxxxxxx> wrote:

[snip]

I have a sequence generated with the following expression

A(x)=(d + a*x) (mod n)

Where 0<=d<n, and a and n are coprimes, i.e gcd(a,n)=1.[snip]

Consider r consecutive values of the sequence A(x)

starting from 0, so {A(0) ... A(r-1)} where 0<=r<n. What I

want to know is how many values of the subset {A(0)

... A(r-1)} are above my threshold j.

An approximate solution would be simple. Do you need an

exact solution? Faster than just counting them?

--

To email me, substitute nowhere->spamcop, invalid->net.

Hi,

What I am looking for is the exact value in a close formula. I need

this in order to proof something, so I am not interested in an

algorithm. Do you have any idea ? An approximation, or better a bound,

can be a starting point.

Best Regards

Dani

Actually what I need to proof is that r/(m-1) is bigger than sth, so I

need a lower bound for r/(m-1). Where r is the lentgh of the sequence,

and m is the number of elements in the sequence {A(0) ... A(r-1)}

above/below the threshold j.

Regards

Daniel

.

**Follow-Ups**:**Re: Question on modular algebra***From:*Mike Amling

**References**:**Question on modular algebra***From:*Dani Camps

**Re: Question on modular algebra***From:*Peter Pearson

**Re: Question on modular algebra***From:*Dani Camps

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