I wont to build a graphical representation of numbers, as "waves":
Similar as the graphic of sin x but for each number N it gets bigger and bigger
crosses the x axes in the multiples of N,
with y from -N to +N
and repeating every 2N.
I found this tool usefull for the drawing:
Can some one help me with finding the function ?
I am not entirely sure what you mean, but I can give you a direction to look.
To change the points where the graph crosses the x-axis, change sin(x) to sin(a*x) for some a. For example sin(pi*x) or the other way round using a division: sin(x/pi).
To make the graphic bigger for bigger x, try adding a factor related to x (like x itself, x^2, sqrt(x), e^x). For example: x*sin(x)