Inspired by the Mathlogger video:

https://www.youtube.com/watch?v=qhbuKbxJsk8

This program makes the circles and lines shown in the video above.

They are made by placing points equally around a circle. The number of points to place is called
the modulus.

Each point is numbered from zero to the modulus minus one. As you go around the second time, each point
also has the number modulus plus its number.

Lines are drawn by taking the point number, multiplying by the given multiplier, and then drawing a
line from that point to the point identified by the new number.

For example, with a multiplier of 3 and a modulus of 10, a line is drawn from point 1 to point 3 (1 * 3),
from point 2 to point 6 (2 * 3), from point 3 to point 9 (3 * 3), from point 4 to point 2 (4 * 3 modulo 10),
and so on.

With this program you can resize the window, enter the multiplier and modulus, and save the resulting image.