This publication 'the golden square', describes how the number Pi is in the square. And with this number Pi (square PI number) I show a third way how to determine the circumference of a circle.
- the pyramid Pi method.
- the pentagram Pi method.
- the square Pi method.
There are now three unique geometrically based Pi numbers, which are unmatchable.
In addition, I show that from the square every angle on the circle can be determined (without protractor) that are equal to each other.
