Pépin's Test/Mistake

Source Work

 * The Dictionary
 * $257$
 * $257$

Mistake

 * Such tests are easily performed today on computers using this criterion, which is similar to Lucas's test for the primality of Mersenne numbers: $F_n$ is prime it divides $3^{1/x \left({F_n - 1}\right)} + 1$.

That last expression should read $3^{1/2 \left({F_n - 1}\right)} + 1$, or more neatly: $3^{\left({F_n - 1}\right) / 2} + 1$.