Constructing the $2^{2^5}+1={\mathbf{F}}_5$-gon, the first step: the 641-gon

Helmut Ruhland

In an article, S. Adlaj showed the construction of the $F_4=65537$-gon ($F_4$ a Fermat prime). By extending the author's method to cases where the multiplicative group is not o…