Finding General Function f(m,n) for Points Graphs

[Emilijo]

Homework Statement

I need to get a general function in 2 variables f(m,n). You can see a graphicon with charasteristic points:
In the first example m=2 (m is period).
https://www.physicsforums.com/attachm...1&d=1329945735
In the next example m=3:
https://www.physicsforums.com/attachm...1&d=1329945822
For m=4:
https://www.physicsforums.com/attachm...1&d=1329945902
and so on.

The task is to find a general function f(m,n) with these terms:
The function has to be periodic.
The function has to include those blue and red points in each example.
The value of the function has to be f(m,n) =1 ONLY in blue points, and the value of the function has to be f(m,n)=0 ONLY in red points.

The look of the function isn't important as long as it complies with previous terms.

Homework Equations

see above

The Attempt at a Solution

try to use absolute, trigonometric functions

 

[80past2]

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