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Brazil Undergrad MO
2017 Brazil Undergrad MO
2
2
Part of
2017 Brazil Undergrad MO
Problems
(1)
Sequence divisible by infinite primes - Brazil Undergrad MO
Source: Brazil Undergrad MO 2017 - Problem 2
11/1/2017
Let
a
a
a
and
b
b
b
be fixed positive integers. Show that the set of primes that divide at least one of the terms of the sequence
a
n
=
a
⋅
201
7
n
+
b
⋅
201
6
n
a_n = a \cdot 2017^n + b \cdot 2016^n
a
n
=
a
⋅
201
7
n
+
b
⋅
201
6
n
is infinite.
number theory
prime numbers
Sequence
Brazilian Undergrad MO