Editing Angle trisection (section)

===Other numbers of parts===
For any nonzero integer {{mvar|N}}, an angle of measure {{math|{{frac|2{{pi}}|''N''}}}} radians can be divided into {{mvar|n}} equal parts with straightedge and compass if and only if {{mvar|n}} is either a power of {{math|2}} or is a power of {{math|2}} multiplied by the product of one or more distinct Fermat primes, none of which divides {{mvar|N}}. In the case of trisection ({{math|''n'' {{=}} 3}}, which is a Fermat prime), this condition becomes the above-mentioned requirement that {{mvar|N}} not be divisible by {{math|3}}.<ref name=McLean/>