# Construction of Regular Prime p-Gon Exists iff p is Fermat Prime/Historical Note

## Historical Note on Construction of Regular Prime $p$-Gon Exists iff $p$ is Fermat Prime

The result Construction of Regular Prime $p$-Gon Exists iff $p$ is Fermat Prime was stated, but not proved, by Carl Friedrich Gauss, who demonstrated the result for $n = 17$ in $1796$, when he was $18$.

The case $p = 257$ was demonstrated by Magnus Georg Paucker in $1822$, and again by Friedrich Julius Richelot in $1832$.

The case $p = 65 \, 537$ was attempted by Johann Gustav Hermes, who offered a construction in $1894$ after a decade of work. However, it has been suggested that there are mistakes in his work.

The cases where $p = 3$ and $p = 5$ were known to the ancient Greeks and are given in Euclid's *The Elements*.

## Sources

- 1937: Eric Temple Bell:
*Men of Mathematics*... (previous) ... (next): Chapter $\text{IV}$: The Prince of Amateurs - 1986: David Wells:
*Curious and Interesting Numbers*... (previous) ... (next): $17$ - 1992: George F. Simmons:
*Calculus Gems*... (previous) ... (next): Chapter $\text {A}.4$: Euclid (flourished ca. $300$ B.C.) - 1992: George F. Simmons:
*Calculus Gems*... (previous) ... (next): Chapter $\text {A}.25$: Gauss ($1777$ – $1855$) - 1997: David Wells:
*Curious and Interesting Numbers*(2nd ed.) ... (previous) ... (next): $17$ - 2008: Ian Stewart:
*Taming the Infinite*... (previous) ... (next): Chapter $7$: Patterns in Numbers