MathDB
Problems
Contests
National and Regional Contests
Switzerland Contests
Switzerland Team Selection Test
2019 Switzerland Team Selection Test
2
Prime Expressible in Root of a Rational
Prime Expressible in Root of a Rational
Source: Swiss TST 2019 P2
May 12, 2020
number theory
prime numbers
Problem Statement
Find the largest prime
p
p
p
such that there exist positive integers
a
,
b
a,b
a
,
b
satisfying
p
=
b
2
a
−
b
a
+
b
.
p=\frac{b}{2}\sqrt{\frac{a-b}{a+b}}.
p
=
2
b
a
+
b
a
−
b
.
Back to Problems
View on AoPS