This is the reason why a half step was take,
a old number of steps is required to reach length 1 at π2 further down. Without the half steps the formulation of L will scream for an even factor.
M=4Nn is an even partition such that integer steps can be taken to N. a is odd because N is odd due to n being odd. b is also odd for the same reason. So c is even such that a+b+c fills up M an even number. But full steps in c cannot reach π2. L is in odd steps only due to N and n being odd. So, a half step is taken to find the step count and c is recovered by doubling the half step count ( times 2).
It is possible instead to step all the way to 3π2 and then divide the count obtained by 3? In this case the expression for length ˉc is3L which is the reciprocal of an integer only if L has a factor 3. This is not the case for prime numbers other then 3, and the prove will fail.
We start not with n dividing a circle, we start with 4 dividing the circle.
Goodnight.