For
with
odd and
, if there exists an integer
such that
then
is prime. A prime of this form is known as a Proth
prime.
For
with
odd and
, if there exists an integer
such that
then
is prime. A prime of this form is known as a Proth
prime.
Weisstein, Eric W. "Proth's Theorem." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/ProthsTheorem.html